2tan (problem 3.3.2)

Percentage Accurate: 62.4% → 99.6%
Time: 12.2s
Alternatives: 10
Speedup: 207.0×

Specification

?
\[\left(\left(-10000 \leq x \land x \leq 10000\right) \land 10^{-16} \cdot \left|x\right| < \varepsilon\right) \land \varepsilon < \left|x\right|\]
\[\begin{array}{l} \\ \tan \left(x + \varepsilon\right) - \tan x \end{array} \]
(FPCore (x eps) :precision binary64 (- (tan (+ x eps)) (tan x)))
double code(double x, double eps) {
	return tan((x + eps)) - tan(x);
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(x, eps)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = tan((x + eps)) - tan(x)
end function
public static double code(double x, double eps) {
	return Math.tan((x + eps)) - Math.tan(x);
}
def code(x, eps):
	return math.tan((x + eps)) - math.tan(x)
function code(x, eps)
	return Float64(tan(Float64(x + eps)) - tan(x))
end
function tmp = code(x, eps)
	tmp = tan((x + eps)) - tan(x);
end
code[x_, eps_] := N[(N[Tan[N[(x + eps), $MachinePrecision]], $MachinePrecision] - N[Tan[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\tan \left(x + \varepsilon\right) - \tan x
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 10 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 62.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \tan \left(x + \varepsilon\right) - \tan x \end{array} \]
(FPCore (x eps) :precision binary64 (- (tan (+ x eps)) (tan x)))
double code(double x, double eps) {
	return tan((x + eps)) - tan(x);
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(x, eps)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = tan((x + eps)) - tan(x)
end function
public static double code(double x, double eps) {
	return Math.tan((x + eps)) - Math.tan(x);
}
def code(x, eps):
	return math.tan((x + eps)) - math.tan(x)
function code(x, eps)
	return Float64(tan(Float64(x + eps)) - tan(x))
end
function tmp = code(x, eps)
	tmp = tan((x + eps)) - tan(x);
end
code[x_, eps_] := N[(N[Tan[N[(x + eps), $MachinePrecision]], $MachinePrecision] - N[Tan[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\tan \left(x + \varepsilon\right) - \tan x
\end{array}

Alternative 1: 99.6% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := {\sin x}^{2}\\ t_1 := {\cos x}^{2}\\ \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\sin x, \frac{\sin x}{t\_1}, 1\right), -0.5, \frac{\mathsf{fma}\left(\mathsf{fma}\left(t\_0, \frac{-1}{t\_1}, -1\right), t\_0, t\_0 \cdot 0.16666666666666666\right)}{t\_1}\right), -1, -0.16666666666666666\right) \cdot \varepsilon, \varepsilon, \frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{t\_0}{t\_1}, \varepsilon, \varepsilon\right), \sin x, \frac{t\_0}{\cos x}\right)}{\cos x}\right), \varepsilon, \varepsilon\right) \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (pow (sin x) 2.0)) (t_1 (pow (cos x) 2.0)))
   (fma
    (fma
     (*
      (fma
       (fma
        (fma (sin x) (/ (sin x) t_1) 1.0)
        -0.5
        (/
         (fma (fma t_0 (/ -1.0 t_1) -1.0) t_0 (* t_0 0.16666666666666666))
         t_1))
       -1.0
       -0.16666666666666666)
      eps)
     eps
     (/ (fma (fma (/ t_0 t_1) eps eps) (sin x) (/ t_0 (cos x))) (cos x)))
    eps
    eps)))
double code(double x, double eps) {
	double t_0 = pow(sin(x), 2.0);
	double t_1 = pow(cos(x), 2.0);
	return fma(fma((fma(fma(fma(sin(x), (sin(x) / t_1), 1.0), -0.5, (fma(fma(t_0, (-1.0 / t_1), -1.0), t_0, (t_0 * 0.16666666666666666)) / t_1)), -1.0, -0.16666666666666666) * eps), eps, (fma(fma((t_0 / t_1), eps, eps), sin(x), (t_0 / cos(x))) / cos(x))), eps, eps);
}
function code(x, eps)
	t_0 = sin(x) ^ 2.0
	t_1 = cos(x) ^ 2.0
	return fma(fma(Float64(fma(fma(fma(sin(x), Float64(sin(x) / t_1), 1.0), -0.5, Float64(fma(fma(t_0, Float64(-1.0 / t_1), -1.0), t_0, Float64(t_0 * 0.16666666666666666)) / t_1)), -1.0, -0.16666666666666666) * eps), eps, Float64(fma(fma(Float64(t_0 / t_1), eps, eps), sin(x), Float64(t_0 / cos(x))) / cos(x))), eps, eps)
end
code[x_, eps_] := Block[{t$95$0 = N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision]}, Block[{t$95$1 = N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]}, N[(N[(N[(N[(N[(N[(N[Sin[x], $MachinePrecision] * N[(N[Sin[x], $MachinePrecision] / t$95$1), $MachinePrecision] + 1.0), $MachinePrecision] * -0.5 + N[(N[(N[(t$95$0 * N[(-1.0 / t$95$1), $MachinePrecision] + -1.0), $MachinePrecision] * t$95$0 + N[(t$95$0 * 0.16666666666666666), $MachinePrecision]), $MachinePrecision] / t$95$1), $MachinePrecision]), $MachinePrecision] * -1.0 + -0.16666666666666666), $MachinePrecision] * eps), $MachinePrecision] * eps + N[(N[(N[(N[(t$95$0 / t$95$1), $MachinePrecision] * eps + eps), $MachinePrecision] * N[Sin[x], $MachinePrecision] + N[(t$95$0 / N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * eps + eps), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := {\sin x}^{2}\\
t_1 := {\cos x}^{2}\\
\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\sin x, \frac{\sin x}{t\_1}, 1\right), -0.5, \frac{\mathsf{fma}\left(\mathsf{fma}\left(t\_0, \frac{-1}{t\_1}, -1\right), t\_0, t\_0 \cdot 0.16666666666666666\right)}{t\_1}\right), -1, -0.16666666666666666\right) \cdot \varepsilon, \varepsilon, \frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{t\_0}{t\_1}, \varepsilon, \varepsilon\right), \sin x, \frac{t\_0}{\cos x}\right)}{\cos x}\right), \varepsilon, \varepsilon\right)
\end{array}
\end{array}
Derivation
  1. Initial program 62.0%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(\frac{1}{6} + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(\frac{-1}{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + \frac{1}{6} \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)\right) - -1 \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Applied rewrites100.0%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\sin x, \frac{\sin x}{{\cos x}^{2}}, 1\right), -0.5, \frac{\mathsf{fma}\left(\mathsf{fma}\left({\sin x}^{2}, \frac{-1}{{\cos x}^{2}}, -1\right), {\sin x}^{2}, {\sin x}^{2} \cdot 0.16666666666666666\right)}{{\cos x}^{2}}\right), -1, -0.16666666666666666\right) \cdot \varepsilon, \varepsilon, \frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{{\sin x}^{2}}{{\cos x}^{2}}, \varepsilon, \varepsilon\right), \sin x, \frac{{\sin x}^{2}}{\cos x}\right)}{\cos x}\right), \varepsilon, \varepsilon\right)} \]
  5. Add Preprocessing

Alternative 2: 99.9% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \frac{\sin \varepsilon}{\cos \left(\varepsilon + x\right) \cdot \cos x} \end{array} \]
(FPCore (x eps) :precision binary64 (/ (sin eps) (* (cos (+ eps x)) (cos x))))
double code(double x, double eps) {
	return sin(eps) / (cos((eps + x)) * cos(x));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(x, eps)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = sin(eps) / (cos((eps + x)) * cos(x))
end function
public static double code(double x, double eps) {
	return Math.sin(eps) / (Math.cos((eps + x)) * Math.cos(x));
}
def code(x, eps):
	return math.sin(eps) / (math.cos((eps + x)) * math.cos(x))
function code(x, eps)
	return Float64(sin(eps) / Float64(cos(Float64(eps + x)) * cos(x)))
end
function tmp = code(x, eps)
	tmp = sin(eps) / (cos((eps + x)) * cos(x));
end
code[x_, eps_] := N[(N[Sin[eps], $MachinePrecision] / N[(N[Cos[N[(eps + x), $MachinePrecision]], $MachinePrecision] * N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\sin \varepsilon}{\cos \left(\varepsilon + x\right) \cdot \cos x}
\end{array}
Derivation
  1. Initial program 62.0%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right) - \tan x} \]
    2. lift-tan.f64N/A

      \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right)} - \tan x \]
    3. tan-quotN/A

      \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)}} - \tan x \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\tan x} \]
    5. tan-quotN/A

      \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\frac{\sin x}{\cos x}} \]
    6. frac-subN/A

      \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
    7. lower-/.f64N/A

      \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
    8. sin-diff-revN/A

      \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
    9. lower-sin.f64N/A

      \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
    10. lower--.f64N/A

      \[\leadsto \frac{\sin \color{blue}{\left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
    11. lift-+.f64N/A

      \[\leadsto \frac{\sin \left(\color{blue}{\left(x + \varepsilon\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
    12. +-commutativeN/A

      \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
    13. lower-+.f64N/A

      \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
    14. lower-*.f64N/A

      \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
    15. lower-cos.f64N/A

      \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right)} \cdot \cos x} \]
    16. lift-+.f64N/A

      \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
    17. +-commutativeN/A

      \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
    18. lower-+.f64N/A

      \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
    19. lower-cos.f6462.1

      \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \color{blue}{\cos x}} \]
  4. Applied rewrites62.1%

    \[\leadsto \color{blue}{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
  5. Taylor expanded in x around 0

    \[\leadsto \frac{\sin \color{blue}{\varepsilon}}{\cos \left(\varepsilon + x\right) \cdot \cos x} \]
  6. Step-by-step derivation
    1. Applied rewrites100.0%

      \[\leadsto \frac{\sin \color{blue}{\varepsilon}}{\cos \left(\varepsilon + x\right) \cdot \cos x} \]
    2. Add Preprocessing

    Alternative 3: 99.4% accurate, 0.9× speedup?

    \[\begin{array}{l} \\ \frac{\varepsilon}{\cos \left(\varepsilon + x\right) \cdot \cos x} \end{array} \]
    (FPCore (x eps) :precision binary64 (/ eps (* (cos (+ eps x)) (cos x))))
    double code(double x, double eps) {
    	return eps / (cos((eps + x)) * cos(x));
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(x, eps)
    use fmin_fmax_functions
        real(8), intent (in) :: x
        real(8), intent (in) :: eps
        code = eps / (cos((eps + x)) * cos(x))
    end function
    
    public static double code(double x, double eps) {
    	return eps / (Math.cos((eps + x)) * Math.cos(x));
    }
    
    def code(x, eps):
    	return eps / (math.cos((eps + x)) * math.cos(x))
    
    function code(x, eps)
    	return Float64(eps / Float64(cos(Float64(eps + x)) * cos(x)))
    end
    
    function tmp = code(x, eps)
    	tmp = eps / (cos((eps + x)) * cos(x));
    end
    
    code[x_, eps_] := N[(eps / N[(N[Cos[N[(eps + x), $MachinePrecision]], $MachinePrecision] * N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \frac{\varepsilon}{\cos \left(\varepsilon + x\right) \cdot \cos x}
    \end{array}
    
    Derivation
    1. Initial program 62.0%

      \[\tan \left(x + \varepsilon\right) - \tan x \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right) - \tan x} \]
      2. lift-tan.f64N/A

        \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right)} - \tan x \]
      3. tan-quotN/A

        \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)}} - \tan x \]
      4. lift-tan.f64N/A

        \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\tan x} \]
      5. tan-quotN/A

        \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\frac{\sin x}{\cos x}} \]
      6. frac-subN/A

        \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
      7. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
      8. sin-diff-revN/A

        \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
      9. lower-sin.f64N/A

        \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
      10. lower--.f64N/A

        \[\leadsto \frac{\sin \color{blue}{\left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
      11. lift-+.f64N/A

        \[\leadsto \frac{\sin \left(\color{blue}{\left(x + \varepsilon\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
      12. +-commutativeN/A

        \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
      13. lower-+.f64N/A

        \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
      14. lower-*.f64N/A

        \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
      15. lower-cos.f64N/A

        \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right)} \cdot \cos x} \]
      16. lift-+.f64N/A

        \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
      17. +-commutativeN/A

        \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
      18. lower-+.f64N/A

        \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
      19. lower-cos.f6462.1

        \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \color{blue}{\cos x}} \]
    4. Applied rewrites62.1%

      \[\leadsto \color{blue}{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
    5. Taylor expanded in eps around 0

      \[\leadsto \frac{\color{blue}{\varepsilon}}{\cos \left(\varepsilon + x\right) \cdot \cos x} \]
    6. Step-by-step derivation
      1. Applied rewrites100.0%

        \[\leadsto \frac{\color{blue}{\varepsilon}}{\cos \left(\varepsilon + x\right) \cdot \cos x} \]
      2. Add Preprocessing

      Alternative 4: 99.0% accurate, 1.7× speedup?

      \[\begin{array}{l} \\ \frac{\varepsilon}{\mathsf{fma}\left(\cos \left(-2 \cdot x\right), 0.5, 0.5\right)} \end{array} \]
      (FPCore (x eps) :precision binary64 (/ eps (fma (cos (* -2.0 x)) 0.5 0.5)))
      double code(double x, double eps) {
      	return eps / fma(cos((-2.0 * x)), 0.5, 0.5);
      }
      
      function code(x, eps)
      	return Float64(eps / fma(cos(Float64(-2.0 * x)), 0.5, 0.5))
      end
      
      code[x_, eps_] := N[(eps / N[(N[Cos[N[(-2.0 * x), $MachinePrecision]], $MachinePrecision] * 0.5 + 0.5), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{\varepsilon}{\mathsf{fma}\left(\cos \left(-2 \cdot x\right), 0.5, 0.5\right)}
      \end{array}
      
      Derivation
      1. Initial program 62.0%

        \[\tan \left(x + \varepsilon\right) - \tan x \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift--.f64N/A

          \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right) - \tan x} \]
        2. lift-tan.f64N/A

          \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right)} - \tan x \]
        3. tan-quotN/A

          \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)}} - \tan x \]
        4. lift-tan.f64N/A

          \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\tan x} \]
        5. tan-quotN/A

          \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\frac{\sin x}{\cos x}} \]
        6. frac-subN/A

          \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
        7. lower-/.f64N/A

          \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
        8. sin-diff-revN/A

          \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
        9. lower-sin.f64N/A

          \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
        10. lower--.f64N/A

          \[\leadsto \frac{\sin \color{blue}{\left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
        11. lift-+.f64N/A

          \[\leadsto \frac{\sin \left(\color{blue}{\left(x + \varepsilon\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
        12. +-commutativeN/A

          \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
        13. lower-+.f64N/A

          \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
        14. lower-*.f64N/A

          \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
        15. lower-cos.f64N/A

          \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right)} \cdot \cos x} \]
        16. lift-+.f64N/A

          \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
        17. +-commutativeN/A

          \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
        18. lower-+.f64N/A

          \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
        19. lower-cos.f6462.1

          \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \color{blue}{\cos x}} \]
      4. Applied rewrites62.1%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
      5. Taylor expanded in eps around 0

        \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
      6. Step-by-step derivation
        1. Applied rewrites99.6%

          \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
        2. Step-by-step derivation
          1. Applied rewrites99.6%

            \[\leadsto \frac{\varepsilon}{0.5 + \color{blue}{0.5 \cdot \cos \left(2 \cdot x\right)}} \]
          2. Step-by-step derivation
            1. Applied rewrites99.6%

              \[\leadsto \frac{\varepsilon}{\mathsf{fma}\left(\cos \left(-2 \cdot x\right), \color{blue}{0.5}, 0.5\right)} \]
            2. Add Preprocessing

            Alternative 5: 98.4% accurate, 4.6× speedup?

            \[\begin{array}{l} \\ \frac{\varepsilon}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.044444444444444446, x \cdot x, 0.3333333333333333\right), x \cdot x, -1\right), x \cdot x, 1\right)} \end{array} \]
            (FPCore (x eps)
             :precision binary64
             (/
              eps
              (fma
               (fma (fma -0.044444444444444446 (* x x) 0.3333333333333333) (* x x) -1.0)
               (* x x)
               1.0)))
            double code(double x, double eps) {
            	return eps / fma(fma(fma(-0.044444444444444446, (x * x), 0.3333333333333333), (x * x), -1.0), (x * x), 1.0);
            }
            
            function code(x, eps)
            	return Float64(eps / fma(fma(fma(-0.044444444444444446, Float64(x * x), 0.3333333333333333), Float64(x * x), -1.0), Float64(x * x), 1.0))
            end
            
            code[x_, eps_] := N[(eps / N[(N[(N[(-0.044444444444444446 * N[(x * x), $MachinePrecision] + 0.3333333333333333), $MachinePrecision] * N[(x * x), $MachinePrecision] + -1.0), $MachinePrecision] * N[(x * x), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \frac{\varepsilon}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.044444444444444446, x \cdot x, 0.3333333333333333\right), x \cdot x, -1\right), x \cdot x, 1\right)}
            \end{array}
            
            Derivation
            1. Initial program 62.0%

              \[\tan \left(x + \varepsilon\right) - \tan x \]
            2. Add Preprocessing
            3. Step-by-step derivation
              1. lift--.f64N/A

                \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right) - \tan x} \]
              2. lift-tan.f64N/A

                \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right)} - \tan x \]
              3. tan-quotN/A

                \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)}} - \tan x \]
              4. lift-tan.f64N/A

                \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\tan x} \]
              5. tan-quotN/A

                \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\frac{\sin x}{\cos x}} \]
              6. frac-subN/A

                \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
              7. lower-/.f64N/A

                \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
              8. sin-diff-revN/A

                \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
              9. lower-sin.f64N/A

                \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
              10. lower--.f64N/A

                \[\leadsto \frac{\sin \color{blue}{\left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
              11. lift-+.f64N/A

                \[\leadsto \frac{\sin \left(\color{blue}{\left(x + \varepsilon\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
              12. +-commutativeN/A

                \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
              13. lower-+.f64N/A

                \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
              14. lower-*.f64N/A

                \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
              15. lower-cos.f64N/A

                \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right)} \cdot \cos x} \]
              16. lift-+.f64N/A

                \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
              17. +-commutativeN/A

                \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
              18. lower-+.f64N/A

                \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
              19. lower-cos.f6462.1

                \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \color{blue}{\cos x}} \]
            4. Applied rewrites62.1%

              \[\leadsto \color{blue}{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
            5. Taylor expanded in eps around 0

              \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
            6. Step-by-step derivation
              1. Applied rewrites99.6%

                \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
              2. Taylor expanded in x around 0

                \[\leadsto \frac{\varepsilon}{1 + \color{blue}{{x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{1}{3} + \frac{-2}{45} \cdot {x}^{2}\right) - 1\right)}} \]
              3. Step-by-step derivation
                1. Applied rewrites99.2%

                  \[\leadsto \frac{\varepsilon}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.044444444444444446, x \cdot x, 0.3333333333333333\right), x \cdot x, -1\right), \color{blue}{x \cdot x}, 1\right)} \]
                2. Add Preprocessing

                Alternative 6: 98.4% accurate, 4.7× speedup?

                \[\begin{array}{l} \\ \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\varepsilon \cdot 0.37777777777777777, x \cdot x, 0.6666666666666666 \cdot \varepsilon\right), x \cdot x, \varepsilon\right), x \cdot x, \varepsilon\right) \end{array} \]
                (FPCore (x eps)
                 :precision binary64
                 (fma
                  (fma
                   (fma (* eps 0.37777777777777777) (* x x) (* 0.6666666666666666 eps))
                   (* x x)
                   eps)
                  (* x x)
                  eps))
                double code(double x, double eps) {
                	return fma(fma(fma((eps * 0.37777777777777777), (x * x), (0.6666666666666666 * eps)), (x * x), eps), (x * x), eps);
                }
                
                function code(x, eps)
                	return fma(fma(fma(Float64(eps * 0.37777777777777777), Float64(x * x), Float64(0.6666666666666666 * eps)), Float64(x * x), eps), Float64(x * x), eps)
                end
                
                code[x_, eps_] := N[(N[(N[(N[(eps * 0.37777777777777777), $MachinePrecision] * N[(x * x), $MachinePrecision] + N[(0.6666666666666666 * eps), $MachinePrecision]), $MachinePrecision] * N[(x * x), $MachinePrecision] + eps), $MachinePrecision] * N[(x * x), $MachinePrecision] + eps), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\varepsilon \cdot 0.37777777777777777, x \cdot x, 0.6666666666666666 \cdot \varepsilon\right), x \cdot x, \varepsilon\right), x \cdot x, \varepsilon\right)
                \end{array}
                
                Derivation
                1. Initial program 62.0%

                  \[\tan \left(x + \varepsilon\right) - \tan x \]
                2. Add Preprocessing
                3. Step-by-step derivation
                  1. lift--.f64N/A

                    \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right) - \tan x} \]
                  2. lift-tan.f64N/A

                    \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right)} - \tan x \]
                  3. tan-quotN/A

                    \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)}} - \tan x \]
                  4. lift-tan.f64N/A

                    \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\tan x} \]
                  5. tan-quotN/A

                    \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\frac{\sin x}{\cos x}} \]
                  6. frac-subN/A

                    \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
                  7. lower-/.f64N/A

                    \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
                  8. sin-diff-revN/A

                    \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                  9. lower-sin.f64N/A

                    \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                  10. lower--.f64N/A

                    \[\leadsto \frac{\sin \color{blue}{\left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                  11. lift-+.f64N/A

                    \[\leadsto \frac{\sin \left(\color{blue}{\left(x + \varepsilon\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                  12. +-commutativeN/A

                    \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                  13. lower-+.f64N/A

                    \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                  14. lower-*.f64N/A

                    \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
                  15. lower-cos.f64N/A

                    \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right)} \cdot \cos x} \]
                  16. lift-+.f64N/A

                    \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
                  17. +-commutativeN/A

                    \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
                  18. lower-+.f64N/A

                    \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
                  19. lower-cos.f6462.1

                    \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \color{blue}{\cos x}} \]
                4. Applied rewrites62.1%

                  \[\leadsto \color{blue}{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
                5. Taylor expanded in eps around 0

                  \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
                6. Step-by-step derivation
                  1. Applied rewrites99.6%

                    \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
                  2. Taylor expanded in x around 0

                    \[\leadsto \varepsilon + \color{blue}{\varepsilon \cdot {x}^{2}} \]
                  3. Step-by-step derivation
                    1. Applied rewrites98.9%

                      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\varepsilon}, \varepsilon\right) \]
                    2. Taylor expanded in x around 0

                      \[\leadsto \varepsilon + \color{blue}{{x}^{2} \cdot \left({x}^{2} \cdot \left(-1 \cdot \left({x}^{2} \cdot \left(-1 \cdot \varepsilon + \left(\frac{-2}{45} \cdot \varepsilon + \frac{2}{3} \cdot \varepsilon\right)\right)\right) - \left(-1 \cdot \varepsilon + \frac{1}{3} \cdot \varepsilon\right)\right) - -1 \cdot \varepsilon\right)} \]
                    3. Step-by-step derivation
                      1. Applied rewrites99.1%

                        \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\varepsilon \cdot 0.37777777777777777, x \cdot x, 0.6666666666666666 \cdot \varepsilon\right), x \cdot x, \varepsilon\right), \color{blue}{x \cdot x}, \varepsilon\right) \]
                      2. Add Preprocessing

                      Alternative 7: 98.4% accurate, 6.1× speedup?

                      \[\begin{array}{l} \\ \frac{\varepsilon}{\mathsf{fma}\left(\mathsf{fma}\left(0.3333333333333333, x \cdot x, -1\right), x \cdot x, 1\right)} \end{array} \]
                      (FPCore (x eps)
                       :precision binary64
                       (/ eps (fma (fma 0.3333333333333333 (* x x) -1.0) (* x x) 1.0)))
                      double code(double x, double eps) {
                      	return eps / fma(fma(0.3333333333333333, (x * x), -1.0), (x * x), 1.0);
                      }
                      
                      function code(x, eps)
                      	return Float64(eps / fma(fma(0.3333333333333333, Float64(x * x), -1.0), Float64(x * x), 1.0))
                      end
                      
                      code[x_, eps_] := N[(eps / N[(N[(0.3333333333333333 * N[(x * x), $MachinePrecision] + -1.0), $MachinePrecision] * N[(x * x), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]
                      
                      \begin{array}{l}
                      
                      \\
                      \frac{\varepsilon}{\mathsf{fma}\left(\mathsf{fma}\left(0.3333333333333333, x \cdot x, -1\right), x \cdot x, 1\right)}
                      \end{array}
                      
                      Derivation
                      1. Initial program 62.0%

                        \[\tan \left(x + \varepsilon\right) - \tan x \]
                      2. Add Preprocessing
                      3. Step-by-step derivation
                        1. lift--.f64N/A

                          \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right) - \tan x} \]
                        2. lift-tan.f64N/A

                          \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right)} - \tan x \]
                        3. tan-quotN/A

                          \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)}} - \tan x \]
                        4. lift-tan.f64N/A

                          \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\tan x} \]
                        5. tan-quotN/A

                          \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\frac{\sin x}{\cos x}} \]
                        6. frac-subN/A

                          \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
                        7. lower-/.f64N/A

                          \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
                        8. sin-diff-revN/A

                          \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                        9. lower-sin.f64N/A

                          \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                        10. lower--.f64N/A

                          \[\leadsto \frac{\sin \color{blue}{\left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                        11. lift-+.f64N/A

                          \[\leadsto \frac{\sin \left(\color{blue}{\left(x + \varepsilon\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                        12. +-commutativeN/A

                          \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                        13. lower-+.f64N/A

                          \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                        14. lower-*.f64N/A

                          \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
                        15. lower-cos.f64N/A

                          \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right)} \cdot \cos x} \]
                        16. lift-+.f64N/A

                          \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
                        17. +-commutativeN/A

                          \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
                        18. lower-+.f64N/A

                          \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
                        19. lower-cos.f6462.1

                          \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \color{blue}{\cos x}} \]
                      4. Applied rewrites62.1%

                        \[\leadsto \color{blue}{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
                      5. Taylor expanded in eps around 0

                        \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
                      6. Step-by-step derivation
                        1. Applied rewrites99.6%

                          \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
                        2. Taylor expanded in x around 0

                          \[\leadsto \frac{\varepsilon}{1 + \color{blue}{{x}^{2} \cdot \left(\frac{1}{3} \cdot {x}^{2} - 1\right)}} \]
                        3. Step-by-step derivation
                          1. Applied rewrites99.1%

                            \[\leadsto \frac{\varepsilon}{\mathsf{fma}\left(\mathsf{fma}\left(0.3333333333333333, x \cdot x, -1\right), \color{blue}{x \cdot x}, 1\right)} \]
                          2. Add Preprocessing

                          Alternative 8: 98.4% accurate, 7.4× speedup?

                          \[\begin{array}{l} \\ \mathsf{fma}\left(\mathsf{fma}\left(0.6666666666666666 \cdot \varepsilon, x \cdot x, \varepsilon\right), x \cdot x, \varepsilon\right) \end{array} \]
                          (FPCore (x eps)
                           :precision binary64
                           (fma (fma (* 0.6666666666666666 eps) (* x x) eps) (* x x) eps))
                          double code(double x, double eps) {
                          	return fma(fma((0.6666666666666666 * eps), (x * x), eps), (x * x), eps);
                          }
                          
                          function code(x, eps)
                          	return fma(fma(Float64(0.6666666666666666 * eps), Float64(x * x), eps), Float64(x * x), eps)
                          end
                          
                          code[x_, eps_] := N[(N[(N[(0.6666666666666666 * eps), $MachinePrecision] * N[(x * x), $MachinePrecision] + eps), $MachinePrecision] * N[(x * x), $MachinePrecision] + eps), $MachinePrecision]
                          
                          \begin{array}{l}
                          
                          \\
                          \mathsf{fma}\left(\mathsf{fma}\left(0.6666666666666666 \cdot \varepsilon, x \cdot x, \varepsilon\right), x \cdot x, \varepsilon\right)
                          \end{array}
                          
                          Derivation
                          1. Initial program 62.0%

                            \[\tan \left(x + \varepsilon\right) - \tan x \]
                          2. Add Preprocessing
                          3. Step-by-step derivation
                            1. lift--.f64N/A

                              \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right) - \tan x} \]
                            2. lift-tan.f64N/A

                              \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right)} - \tan x \]
                            3. tan-quotN/A

                              \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)}} - \tan x \]
                            4. lift-tan.f64N/A

                              \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\tan x} \]
                            5. tan-quotN/A

                              \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\frac{\sin x}{\cos x}} \]
                            6. frac-subN/A

                              \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
                            7. lower-/.f64N/A

                              \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
                            8. sin-diff-revN/A

                              \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                            9. lower-sin.f64N/A

                              \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                            10. lower--.f64N/A

                              \[\leadsto \frac{\sin \color{blue}{\left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                            11. lift-+.f64N/A

                              \[\leadsto \frac{\sin \left(\color{blue}{\left(x + \varepsilon\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                            12. +-commutativeN/A

                              \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                            13. lower-+.f64N/A

                              \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                            14. lower-*.f64N/A

                              \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
                            15. lower-cos.f64N/A

                              \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right)} \cdot \cos x} \]
                            16. lift-+.f64N/A

                              \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
                            17. +-commutativeN/A

                              \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
                            18. lower-+.f64N/A

                              \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
                            19. lower-cos.f6462.1

                              \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \color{blue}{\cos x}} \]
                          4. Applied rewrites62.1%

                            \[\leadsto \color{blue}{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
                          5. Taylor expanded in eps around 0

                            \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
                          6. Step-by-step derivation
                            1. Applied rewrites99.6%

                              \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
                            2. Taylor expanded in x around 0

                              \[\leadsto \varepsilon + \color{blue}{{x}^{2} \cdot \left(-1 \cdot \left({x}^{2} \cdot \left(-1 \cdot \varepsilon + \frac{1}{3} \cdot \varepsilon\right)\right) - -1 \cdot \varepsilon\right)} \]
                            3. Step-by-step derivation
                              1. Applied rewrites99.0%

                                \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\left(\left(-x\right) \cdot x\right) \cdot \varepsilon, -0.6666666666666666, \varepsilon\right), \color{blue}{x \cdot x}, \varepsilon\right) \]
                              2. Taylor expanded in x around 0

                                \[\leadsto \mathsf{fma}\left(\varepsilon + \frac{2}{3} \cdot \left(\varepsilon \cdot {x}^{2}\right), x \cdot x, \varepsilon\right) \]
                              3. Applied rewrites99.0%

                                \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(0.6666666666666666 \cdot \varepsilon, x \cdot x, \varepsilon\right), x \cdot x, \varepsilon\right) \]
                              4. Add Preprocessing

                              Alternative 9: 98.3% accurate, 17.3× speedup?

                              \[\begin{array}{l} \\ \mathsf{fma}\left(x \cdot x, \varepsilon, \varepsilon\right) \end{array} \]
                              (FPCore (x eps) :precision binary64 (fma (* x x) eps eps))
                              double code(double x, double eps) {
                              	return fma((x * x), eps, eps);
                              }
                              
                              function code(x, eps)
                              	return fma(Float64(x * x), eps, eps)
                              end
                              
                              code[x_, eps_] := N[(N[(x * x), $MachinePrecision] * eps + eps), $MachinePrecision]
                              
                              \begin{array}{l}
                              
                              \\
                              \mathsf{fma}\left(x \cdot x, \varepsilon, \varepsilon\right)
                              \end{array}
                              
                              Derivation
                              1. Initial program 62.0%

                                \[\tan \left(x + \varepsilon\right) - \tan x \]
                              2. Add Preprocessing
                              3. Step-by-step derivation
                                1. lift--.f64N/A

                                  \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right) - \tan x} \]
                                2. lift-tan.f64N/A

                                  \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right)} - \tan x \]
                                3. tan-quotN/A

                                  \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)}} - \tan x \]
                                4. lift-tan.f64N/A

                                  \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\tan x} \]
                                5. tan-quotN/A

                                  \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\frac{\sin x}{\cos x}} \]
                                6. frac-subN/A

                                  \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
                                7. lower-/.f64N/A

                                  \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
                                8. sin-diff-revN/A

                                  \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                                9. lower-sin.f64N/A

                                  \[\leadsto \frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                                10. lower--.f64N/A

                                  \[\leadsto \frac{\sin \color{blue}{\left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                                11. lift-+.f64N/A

                                  \[\leadsto \frac{\sin \left(\color{blue}{\left(x + \varepsilon\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                                12. +-commutativeN/A

                                  \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                                13. lower-+.f64N/A

                                  \[\leadsto \frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right) \cdot \cos x} \]
                                14. lower-*.f64N/A

                                  \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
                                15. lower-cos.f64N/A

                                  \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right)} \cdot \cos x} \]
                                16. lift-+.f64N/A

                                  \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
                                17. +-commutativeN/A

                                  \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
                                18. lower-+.f64N/A

                                  \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
                                19. lower-cos.f6462.1

                                  \[\leadsto \frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \color{blue}{\cos x}} \]
                              4. Applied rewrites62.1%

                                \[\leadsto \color{blue}{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
                              5. Taylor expanded in eps around 0

                                \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
                              6. Step-by-step derivation
                                1. Applied rewrites99.6%

                                  \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
                                2. Taylor expanded in x around 0

                                  \[\leadsto \varepsilon + \color{blue}{\varepsilon \cdot {x}^{2}} \]
                                3. Step-by-step derivation
                                  1. Applied rewrites98.9%

                                    \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\varepsilon}, \varepsilon\right) \]
                                  2. Add Preprocessing

                                  Alternative 10: 97.8% accurate, 207.0× speedup?

                                  \[\begin{array}{l} \\ \varepsilon \end{array} \]
                                  (FPCore (x eps) :precision binary64 eps)
                                  double code(double x, double eps) {
                                  	return eps;
                                  }
                                  
                                  module fmin_fmax_functions
                                      implicit none
                                      private
                                      public fmax
                                      public fmin
                                  
                                      interface fmax
                                          module procedure fmax88
                                          module procedure fmax44
                                          module procedure fmax84
                                          module procedure fmax48
                                      end interface
                                      interface fmin
                                          module procedure fmin88
                                          module procedure fmin44
                                          module procedure fmin84
                                          module procedure fmin48
                                      end interface
                                  contains
                                      real(8) function fmax88(x, y) result (res)
                                          real(8), intent (in) :: x
                                          real(8), intent (in) :: y
                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                      end function
                                      real(4) function fmax44(x, y) result (res)
                                          real(4), intent (in) :: x
                                          real(4), intent (in) :: y
                                          res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                      end function
                                      real(8) function fmax84(x, y) result(res)
                                          real(8), intent (in) :: x
                                          real(4), intent (in) :: y
                                          res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                      end function
                                      real(8) function fmax48(x, y) result(res)
                                          real(4), intent (in) :: x
                                          real(8), intent (in) :: y
                                          res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                      end function
                                      real(8) function fmin88(x, y) result (res)
                                          real(8), intent (in) :: x
                                          real(8), intent (in) :: y
                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                      end function
                                      real(4) function fmin44(x, y) result (res)
                                          real(4), intent (in) :: x
                                          real(4), intent (in) :: y
                                          res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                      end function
                                      real(8) function fmin84(x, y) result(res)
                                          real(8), intent (in) :: x
                                          real(4), intent (in) :: y
                                          res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                      end function
                                      real(8) function fmin48(x, y) result(res)
                                          real(4), intent (in) :: x
                                          real(8), intent (in) :: y
                                          res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                      end function
                                  end module
                                  
                                  real(8) function code(x, eps)
                                  use fmin_fmax_functions
                                      real(8), intent (in) :: x
                                      real(8), intent (in) :: eps
                                      code = eps
                                  end function
                                  
                                  public static double code(double x, double eps) {
                                  	return eps;
                                  }
                                  
                                  def code(x, eps):
                                  	return eps
                                  
                                  function code(x, eps)
                                  	return eps
                                  end
                                  
                                  function tmp = code(x, eps)
                                  	tmp = eps;
                                  end
                                  
                                  code[x_, eps_] := eps
                                  
                                  \begin{array}{l}
                                  
                                  \\
                                  \varepsilon
                                  \end{array}
                                  
                                  Derivation
                                  1. Initial program 62.0%

                                    \[\tan \left(x + \varepsilon\right) - \tan x \]
                                  2. Add Preprocessing
                                  3. Taylor expanded in x around 0

                                    \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \varepsilon}} \]
                                  4. Step-by-step derivation
                                    1. Applied rewrites98.4%

                                      \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \varepsilon}} \]
                                    2. Taylor expanded in eps around 0

                                      \[\leadsto \varepsilon \]
                                    3. Step-by-step derivation
                                      1. Applied rewrites98.4%

                                        \[\leadsto \varepsilon \]
                                      2. Add Preprocessing

                                      Developer Target 1: 99.0% accurate, 1.0× speedup?

                                      \[\begin{array}{l} \\ \varepsilon + \left(\varepsilon \cdot \tan x\right) \cdot \tan x \end{array} \]
                                      (FPCore (x eps) :precision binary64 (+ eps (* (* eps (tan x)) (tan x))))
                                      double code(double x, double eps) {
                                      	return eps + ((eps * tan(x)) * tan(x));
                                      }
                                      
                                      module fmin_fmax_functions
                                          implicit none
                                          private
                                          public fmax
                                          public fmin
                                      
                                          interface fmax
                                              module procedure fmax88
                                              module procedure fmax44
                                              module procedure fmax84
                                              module procedure fmax48
                                          end interface
                                          interface fmin
                                              module procedure fmin88
                                              module procedure fmin44
                                              module procedure fmin84
                                              module procedure fmin48
                                          end interface
                                      contains
                                          real(8) function fmax88(x, y) result (res)
                                              real(8), intent (in) :: x
                                              real(8), intent (in) :: y
                                              res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                          end function
                                          real(4) function fmax44(x, y) result (res)
                                              real(4), intent (in) :: x
                                              real(4), intent (in) :: y
                                              res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                          end function
                                          real(8) function fmax84(x, y) result(res)
                                              real(8), intent (in) :: x
                                              real(4), intent (in) :: y
                                              res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                          end function
                                          real(8) function fmax48(x, y) result(res)
                                              real(4), intent (in) :: x
                                              real(8), intent (in) :: y
                                              res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                          end function
                                          real(8) function fmin88(x, y) result (res)
                                              real(8), intent (in) :: x
                                              real(8), intent (in) :: y
                                              res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                          end function
                                          real(4) function fmin44(x, y) result (res)
                                              real(4), intent (in) :: x
                                              real(4), intent (in) :: y
                                              res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                          end function
                                          real(8) function fmin84(x, y) result(res)
                                              real(8), intent (in) :: x
                                              real(4), intent (in) :: y
                                              res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                          end function
                                          real(8) function fmin48(x, y) result(res)
                                              real(4), intent (in) :: x
                                              real(8), intent (in) :: y
                                              res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                          end function
                                      end module
                                      
                                      real(8) function code(x, eps)
                                      use fmin_fmax_functions
                                          real(8), intent (in) :: x
                                          real(8), intent (in) :: eps
                                          code = eps + ((eps * tan(x)) * tan(x))
                                      end function
                                      
                                      public static double code(double x, double eps) {
                                      	return eps + ((eps * Math.tan(x)) * Math.tan(x));
                                      }
                                      
                                      def code(x, eps):
                                      	return eps + ((eps * math.tan(x)) * math.tan(x))
                                      
                                      function code(x, eps)
                                      	return Float64(eps + Float64(Float64(eps * tan(x)) * tan(x)))
                                      end
                                      
                                      function tmp = code(x, eps)
                                      	tmp = eps + ((eps * tan(x)) * tan(x));
                                      end
                                      
                                      code[x_, eps_] := N[(eps + N[(N[(eps * N[Tan[x], $MachinePrecision]), $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                                      
                                      \begin{array}{l}
                                      
                                      \\
                                      \varepsilon + \left(\varepsilon \cdot \tan x\right) \cdot \tan x
                                      \end{array}
                                      

                                      Reproduce

                                      ?
                                      herbie shell --seed 2025019 
                                      (FPCore (x eps)
                                        :name "2tan (problem 3.3.2)"
                                        :precision binary64
                                        :pre (and (and (and (<= -10000.0 x) (<= x 10000.0)) (< (* 1e-16 (fabs x)) eps)) (< eps (fabs x)))
                                      
                                        :alt
                                        (! :herbie-platform default (+ eps (* eps (tan x) (tan x))))
                                      
                                        (- (tan (+ x eps)) (tan x)))