2tan (problem 3.3.2)

Percentage Accurate: 62.4% → 99.9%
Time: 17.5s
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);
}
real(8) function code(x, eps)
    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);
}
real(8) function code(x, eps)
    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: 99.9% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \frac{\sin \varepsilon}{\cos x \cdot \cos \left(\varepsilon + x\right)} \end{array} \]
(FPCore (x eps) :precision binary64 (/ (sin eps) (* (cos x) (cos (+ eps x)))))
double code(double x, double eps) {
	return sin(eps) / (cos(x) * cos((eps + x)));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = sin(eps) / (cos(x) * cos((eps + x)))
end function
public static double code(double x, double eps) {
	return Math.sin(eps) / (Math.cos(x) * Math.cos((eps + x)));
}
def code(x, eps):
	return math.sin(eps) / (math.cos(x) * math.cos((eps + x)))
function code(x, eps)
	return Float64(sin(eps) / Float64(cos(x) * cos(Float64(eps + x))))
end
function tmp = code(x, eps)
	tmp = sin(eps) / (cos(x) * cos((eps + x)));
end
code[x_, eps_] := N[(N[Sin[eps], $MachinePrecision] / N[(N[Cos[x], $MachinePrecision] * N[Cos[N[(eps + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\sin \varepsilon}{\cos x \cdot \cos \left(\varepsilon + x\right)}
\end{array}
Derivation
  1. Initial program 61.3%

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

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

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

      \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
    4. associate-/r*N/A

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

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

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

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

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

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

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

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

      \[\leadsto \frac{\frac{\sin \left(\left(x + \varepsilon\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)}}}{\cos x} \]
    13. cos-lowering-cos.f6461.3

      \[\leadsto \frac{\frac{\sin \left(\left(x + \varepsilon\right) - x\right)}{\cos \left(x + \varepsilon\right)}}{\color{blue}{\cos x}} \]
  4. Applied egg-rr61.3%

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

    \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos x \cdot \cos \left(\varepsilon + x\right)}} \]
  6. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \frac{\sin \varepsilon}{\cos x \cdot \cos \color{blue}{\left(x + \varepsilon\right)}} \]
    2. remove-double-negN/A

      \[\leadsto \frac{\sin \varepsilon}{\cos x \cdot \cos \left(x + \color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\varepsilon\right)\right)\right)\right)}\right)} \]
    3. mul-1-negN/A

      \[\leadsto \frac{\sin \varepsilon}{\cos x \cdot \cos \left(x + \left(\mathsf{neg}\left(\color{blue}{-1 \cdot \varepsilon}\right)\right)\right)} \]
    4. sub-negN/A

      \[\leadsto \frac{\sin \varepsilon}{\cos x \cdot \cos \color{blue}{\left(x - -1 \cdot \varepsilon\right)}} \]
    5. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos x \cdot \cos \left(x - -1 \cdot \varepsilon\right)}} \]
    6. sin-lowering-sin.f64N/A

      \[\leadsto \frac{\color{blue}{\sin \varepsilon}}{\cos x \cdot \cos \left(x - -1 \cdot \varepsilon\right)} \]
    7. *-lowering-*.f64N/A

      \[\leadsto \frac{\sin \varepsilon}{\color{blue}{\cos x \cdot \cos \left(x - -1 \cdot \varepsilon\right)}} \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \frac{\sin \varepsilon}{\color{blue}{\cos x} \cdot \cos \left(x - -1 \cdot \varepsilon\right)} \]
    9. sub-negN/A

      \[\leadsto \frac{\sin \varepsilon}{\cos x \cdot \cos \color{blue}{\left(x + \left(\mathsf{neg}\left(-1 \cdot \varepsilon\right)\right)\right)}} \]
    10. mul-1-negN/A

      \[\leadsto \frac{\sin \varepsilon}{\cos x \cdot \cos \left(x + \left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(\varepsilon\right)\right)}\right)\right)\right)} \]
    11. remove-double-negN/A

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

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

      \[\leadsto \frac{\sin \varepsilon}{\cos x \cdot \color{blue}{\cos \left(\varepsilon + x\right)}} \]
    14. +-lowering-+.f64100.0

      \[\leadsto \frac{\sin \varepsilon}{\cos x \cdot \cos \color{blue}{\left(\varepsilon + x\right)}} \]
  7. Simplified100.0%

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

Alternative 2: 99.7% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon \cdot \varepsilon, 0.008333333333333333, -0.16666666666666666\right), 1\right)}{\cos \left(\varepsilon + x\right)}}{\cos x} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (/
  (/
   (*
    eps
    (fma
     (* eps eps)
     (fma (* eps eps) 0.008333333333333333 -0.16666666666666666)
     1.0))
   (cos (+ eps x)))
  (cos x)))
double code(double x, double eps) {
	return ((eps * fma((eps * eps), fma((eps * eps), 0.008333333333333333, -0.16666666666666666), 1.0)) / cos((eps + x))) / cos(x);
}
function code(x, eps)
	return Float64(Float64(Float64(eps * fma(Float64(eps * eps), fma(Float64(eps * eps), 0.008333333333333333, -0.16666666666666666), 1.0)) / cos(Float64(eps + x))) / cos(x))
end
code[x_, eps_] := N[(N[(N[(eps * N[(N[(eps * eps), $MachinePrecision] * N[(N[(eps * eps), $MachinePrecision] * 0.008333333333333333 + -0.16666666666666666), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision] / N[Cos[N[(eps + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon \cdot \varepsilon, 0.008333333333333333, -0.16666666666666666\right), 1\right)}{\cos \left(\varepsilon + x\right)}}{\cos x}
\end{array}
Derivation
  1. Initial program 61.3%

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

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

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

      \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
    4. associate-/r*N/A

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

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

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

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

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

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

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

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

      \[\leadsto \frac{\frac{\sin \left(\left(x + \varepsilon\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)}}}{\cos x} \]
    13. cos-lowering-cos.f6461.3

      \[\leadsto \frac{\frac{\sin \left(\left(x + \varepsilon\right) - x\right)}{\cos \left(x + \varepsilon\right)}}{\color{blue}{\cos x}} \]
  4. Applied egg-rr61.3%

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

    \[\leadsto \frac{\frac{\color{blue}{\varepsilon \cdot \left(1 + {\varepsilon}^{2} \cdot \left(\frac{1}{120} \cdot {\varepsilon}^{2} - \frac{1}{6}\right)\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
  6. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \frac{\frac{\color{blue}{\varepsilon \cdot \left(1 + {\varepsilon}^{2} \cdot \left(\frac{1}{120} \cdot {\varepsilon}^{2} - \frac{1}{6}\right)\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    2. +-commutativeN/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \color{blue}{\left({\varepsilon}^{2} \cdot \left(\frac{1}{120} \cdot {\varepsilon}^{2} - \frac{1}{6}\right) + 1\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    3. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \color{blue}{\mathsf{fma}\left({\varepsilon}^{2}, \frac{1}{120} \cdot {\varepsilon}^{2} - \frac{1}{6}, 1\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    4. unpow2N/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\color{blue}{\varepsilon \cdot \varepsilon}, \frac{1}{120} \cdot {\varepsilon}^{2} - \frac{1}{6}, 1\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    5. *-lowering-*.f64N/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\color{blue}{\varepsilon \cdot \varepsilon}, \frac{1}{120} \cdot {\varepsilon}^{2} - \frac{1}{6}, 1\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    6. sub-negN/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \color{blue}{\frac{1}{120} \cdot {\varepsilon}^{2} + \left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}, 1\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    7. *-commutativeN/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \color{blue}{{\varepsilon}^{2} \cdot \frac{1}{120}} + \left(\mathsf{neg}\left(\frac{1}{6}\right)\right), 1\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    8. metadata-evalN/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, {\varepsilon}^{2} \cdot \frac{1}{120} + \color{blue}{\frac{-1}{6}}, 1\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    9. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \color{blue}{\mathsf{fma}\left({\varepsilon}^{2}, \frac{1}{120}, \frac{-1}{6}\right)}, 1\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    10. unpow2N/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\color{blue}{\varepsilon \cdot \varepsilon}, \frac{1}{120}, \frac{-1}{6}\right), 1\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    11. *-lowering-*.f64100.0

      \[\leadsto \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\color{blue}{\varepsilon \cdot \varepsilon}, 0.008333333333333333, -0.16666666666666666\right), 1\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
  7. Simplified100.0%

    \[\leadsto \frac{\frac{\color{blue}{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon \cdot \varepsilon, 0.008333333333333333, -0.16666666666666666\right), 1\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
  8. Final simplification100.0%

    \[\leadsto \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, \mathsf{fma}\left(\varepsilon \cdot \varepsilon, 0.008333333333333333, -0.16666666666666666\right), 1\right)}{\cos \left(\varepsilon + x\right)}}{\cos x} \]
  9. Add Preprocessing

Alternative 3: 99.6% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.16666666666666666, 1\right)}{\cos \left(\varepsilon + x\right)}}{\cos x} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (/
  (/ (* eps (fma (* eps eps) -0.16666666666666666 1.0)) (cos (+ eps x)))
  (cos x)))
double code(double x, double eps) {
	return ((eps * fma((eps * eps), -0.16666666666666666, 1.0)) / cos((eps + x))) / cos(x);
}
function code(x, eps)
	return Float64(Float64(Float64(eps * fma(Float64(eps * eps), -0.16666666666666666, 1.0)) / cos(Float64(eps + x))) / cos(x))
end
code[x_, eps_] := N[(N[(N[(eps * N[(N[(eps * eps), $MachinePrecision] * -0.16666666666666666 + 1.0), $MachinePrecision]), $MachinePrecision] / N[Cos[N[(eps + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.16666666666666666, 1\right)}{\cos \left(\varepsilon + x\right)}}{\cos x}
\end{array}
Derivation
  1. Initial program 61.3%

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

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

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

      \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
    4. associate-/r*N/A

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

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

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

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

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

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

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

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

      \[\leadsto \frac{\frac{\sin \left(\left(x + \varepsilon\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)}}}{\cos x} \]
    13. cos-lowering-cos.f6461.3

      \[\leadsto \frac{\frac{\sin \left(\left(x + \varepsilon\right) - x\right)}{\cos \left(x + \varepsilon\right)}}{\color{blue}{\cos x}} \]
  4. Applied egg-rr61.3%

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

    \[\leadsto \frac{\frac{\color{blue}{\varepsilon \cdot \left(1 + \frac{-1}{6} \cdot {\varepsilon}^{2}\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
  6. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \frac{\frac{\color{blue}{\varepsilon \cdot \left(1 + \frac{-1}{6} \cdot {\varepsilon}^{2}\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    2. +-commutativeN/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \color{blue}{\left(\frac{-1}{6} \cdot {\varepsilon}^{2} + 1\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    3. *-commutativeN/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \left(\color{blue}{{\varepsilon}^{2} \cdot \frac{-1}{6}} + 1\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    4. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \color{blue}{\mathsf{fma}\left({\varepsilon}^{2}, \frac{-1}{6}, 1\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    5. unpow2N/A

      \[\leadsto \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\color{blue}{\varepsilon \cdot \varepsilon}, \frac{-1}{6}, 1\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    6. *-lowering-*.f6499.9

      \[\leadsto \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\color{blue}{\varepsilon \cdot \varepsilon}, -0.16666666666666666, 1\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
  7. Simplified99.9%

    \[\leadsto \frac{\frac{\color{blue}{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.16666666666666666, 1\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
  8. Final simplification99.9%

    \[\leadsto \frac{\frac{\varepsilon \cdot \mathsf{fma}\left(\varepsilon \cdot \varepsilon, -0.16666666666666666, 1\right)}{\cos \left(\varepsilon + x\right)}}{\cos x} \]
  9. Add Preprocessing

Alternative 4: 99.3% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \frac{\frac{\varepsilon}{\cos \left(\varepsilon + x\right)}}{\cos x} \end{array} \]
(FPCore (x eps) :precision binary64 (/ (/ eps (cos (+ eps x))) (cos x)))
double code(double x, double eps) {
	return (eps / cos((eps + x))) / cos(x);
}
real(8) function code(x, eps)
    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(Float64(eps / cos(Float64(eps + x))) / cos(x))
end
function tmp = code(x, eps)
	tmp = (eps / cos((eps + x))) / cos(x);
end
code[x_, eps_] := N[(N[(eps / N[Cos[N[(eps + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{\varepsilon}{\cos \left(\varepsilon + x\right)}}{\cos x}
\end{array}
Derivation
  1. Initial program 61.3%

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

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

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

      \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
    4. associate-/r*N/A

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

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

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

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

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

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

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

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

      \[\leadsto \frac{\frac{\sin \left(\left(x + \varepsilon\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)}}}{\cos x} \]
    13. cos-lowering-cos.f6461.3

      \[\leadsto \frac{\frac{\sin \left(\left(x + \varepsilon\right) - x\right)}{\cos \left(x + \varepsilon\right)}}{\color{blue}{\cos x}} \]
  4. Applied egg-rr61.3%

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

    \[\leadsto \frac{\frac{\color{blue}{\varepsilon}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
  6. Step-by-step derivation
    1. Simplified99.7%

      \[\leadsto \frac{\frac{\color{blue}{\varepsilon}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    2. Final simplification99.7%

      \[\leadsto \frac{\frac{\varepsilon}{\cos \left(\varepsilon + x\right)}}{\cos x} \]
    3. Add Preprocessing

    Alternative 5: 98.9% accurate, 1.0× speedup?

    \[\begin{array}{l} \\ \frac{\varepsilon}{{\cos x}^{2}} \end{array} \]
    (FPCore (x eps) :precision binary64 (/ eps (pow (cos x) 2.0)))
    double code(double x, double eps) {
    	return eps / pow(cos(x), 2.0);
    }
    
    real(8) function code(x, eps)
        real(8), intent (in) :: x
        real(8), intent (in) :: eps
        code = eps / (cos(x) ** 2.0d0)
    end function
    
    public static double code(double x, double eps) {
    	return eps / Math.pow(Math.cos(x), 2.0);
    }
    
    def code(x, eps):
    	return eps / math.pow(math.cos(x), 2.0)
    
    function code(x, eps)
    	return Float64(eps / (cos(x) ^ 2.0))
    end
    
    function tmp = code(x, eps)
    	tmp = eps / (cos(x) ^ 2.0);
    end
    
    code[x_, eps_] := N[(eps / N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \frac{\varepsilon}{{\cos x}^{2}}
    \end{array}
    
    Derivation
    1. Initial program 61.3%

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

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

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

        \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
      4. associate-/r*N/A

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

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

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

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

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

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

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

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

        \[\leadsto \frac{\frac{\sin \left(\left(x + \varepsilon\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)}}}{\cos x} \]
      13. cos-lowering-cos.f6461.3

        \[\leadsto \frac{\frac{\sin \left(\left(x + \varepsilon\right) - x\right)}{\cos \left(x + \varepsilon\right)}}{\color{blue}{\cos x}} \]
    4. Applied egg-rr61.3%

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

      \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
    6. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
      2. pow-lowering-pow.f64N/A

        \[\leadsto \frac{\varepsilon}{\color{blue}{{\cos x}^{2}}} \]
      3. cos-lowering-cos.f6499.3

        \[\leadsto \frac{\varepsilon}{{\color{blue}{\cos x}}^{2}} \]
    7. Simplified99.3%

      \[\leadsto \color{blue}{\frac{\varepsilon}{{\cos x}^{2}}} \]
    8. Add Preprocessing

    Alternative 6: 98.3% accurate, 5.9× speedup?

    \[\begin{array}{l} \\ \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, x \cdot 1.3333333333333333, 0.3333333333333333\right), x\right), x \cdot x\right), \varepsilon\right) \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (fma
      eps
      (fma
       eps
       (fma eps (fma x (* x 1.3333333333333333) 0.3333333333333333) x)
       (* x x))
      eps))
    double code(double x, double eps) {
    	return fma(eps, fma(eps, fma(eps, fma(x, (x * 1.3333333333333333), 0.3333333333333333), x), (x * x)), eps);
    }
    
    function code(x, eps)
    	return fma(eps, fma(eps, fma(eps, fma(x, Float64(x * 1.3333333333333333), 0.3333333333333333), x), Float64(x * x)), eps)
    end
    
    code[x_, eps_] := N[(eps * N[(eps * N[(eps * N[(x * N[(x * 1.3333333333333333), $MachinePrecision] + 0.3333333333333333), $MachinePrecision] + x), $MachinePrecision] + N[(x * x), $MachinePrecision]), $MachinePrecision] + eps), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, x \cdot 1.3333333333333333, 0.3333333333333333\right), x\right), x \cdot x\right), \varepsilon\right)
    \end{array}
    
    Derivation
    1. Initial program 61.3%

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

      \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x} + \left(\frac{1}{6} \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x} + \frac{\sin x \cdot \left(\frac{1}{6} + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(\frac{-1}{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + \frac{1}{6} \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)}{\cos x}\right)\right)\right) - \left(\frac{1}{6} + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(\frac{-1}{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + \frac{1}{6} \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)\right) - -1 \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
    4. Simplified99.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(0.3333333333333333, \frac{\sin x + \frac{{\sin x}^{3}}{{\cos x}^{2}}}{\cos x}, \left(\frac{{\sin x}^{2} + \frac{{\sin x}^{4}}{{\cos x}^{2}}}{{\cos x}^{2}} - \left(0.16666666666666666 + \mathsf{fma}\left(0.16666666666666666, \frac{{\sin x}^{2}}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, \frac{{\sin x}^{2}}{{\cos x}^{2}}, -0.5\right)\right)\right)\right) \cdot \frac{\sin x}{\cos x}\right), \frac{{\sin x}^{2} + \frac{{\sin x}^{4}}{{\cos x}^{2}}}{{\cos x}^{2}} - \left(0.16666666666666666 + \mathsf{fma}\left(0.16666666666666666, \frac{{\sin x}^{2}}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, \frac{{\sin x}^{2}}{{\cos x}^{2}}, -0.5\right)\right)\right)\right), \frac{\sin x + \frac{{\sin x}^{3}}{{\cos x}^{2}}}{\cos x}\right), \frac{{\sin x}^{2}}{{\cos x}^{2}}\right), \varepsilon\right)} \]
    5. Taylor expanded in x around 0

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\frac{1}{3} \cdot {\varepsilon}^{2} + x \cdot \left(\varepsilon \cdot \left(1 + \frac{2}{3} \cdot {\varepsilon}^{2}\right) + x \cdot \left(1 + \frac{4}{3} \cdot {\varepsilon}^{2}\right)\right)}, \varepsilon\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{x \cdot \left(\varepsilon \cdot \left(1 + \frac{2}{3} \cdot {\varepsilon}^{2}\right) + x \cdot \left(1 + \frac{4}{3} \cdot {\varepsilon}^{2}\right)\right) + \frac{1}{3} \cdot {\varepsilon}^{2}}, \varepsilon\right) \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(x, \varepsilon \cdot \left(1 + \frac{2}{3} \cdot {\varepsilon}^{2}\right) + x \cdot \left(1 + \frac{4}{3} \cdot {\varepsilon}^{2}\right), \frac{1}{3} \cdot {\varepsilon}^{2}\right)}, \varepsilon\right) \]
    7. Simplified98.9%

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 1.3333333333333333, 1\right), \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.6666666666666666, 1\right)\right), 0.3333333333333333 \cdot \left(\varepsilon \cdot \varepsilon\right)\right)}, \varepsilon\right) \]
    8. Taylor expanded in eps around 0

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\varepsilon \cdot \left(x + \varepsilon \cdot \left(\frac{1}{3} + \frac{4}{3} \cdot {x}^{2}\right)\right) + {x}^{2}}, \varepsilon\right) \]
    9. Step-by-step derivation
      1. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(\varepsilon, x + \varepsilon \cdot \left(\frac{1}{3} + \frac{4}{3} \cdot {x}^{2}\right), {x}^{2}\right)}, \varepsilon\right) \]
      2. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \color{blue}{\varepsilon \cdot \left(\frac{1}{3} + \frac{4}{3} \cdot {x}^{2}\right) + x}, {x}^{2}\right), \varepsilon\right) \]
      3. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(\varepsilon, \frac{1}{3} + \frac{4}{3} \cdot {x}^{2}, x\right)}, {x}^{2}\right), \varepsilon\right) \]
      4. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \color{blue}{\frac{4}{3} \cdot {x}^{2} + \frac{1}{3}}, x\right), {x}^{2}\right), \varepsilon\right) \]
      5. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \color{blue}{{x}^{2} \cdot \frac{4}{3}} + \frac{1}{3}, x\right), {x}^{2}\right), \varepsilon\right) \]
      6. unpow2N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \color{blue}{\left(x \cdot x\right)} \cdot \frac{4}{3} + \frac{1}{3}, x\right), {x}^{2}\right), \varepsilon\right) \]
      7. associate-*l*N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \color{blue}{x \cdot \left(x \cdot \frac{4}{3}\right)} + \frac{1}{3}, x\right), {x}^{2}\right), \varepsilon\right) \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, x \cdot \color{blue}{\left(\frac{4}{3} \cdot x\right)} + \frac{1}{3}, x\right), {x}^{2}\right), \varepsilon\right) \]
      9. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(x, \frac{4}{3} \cdot x, \frac{1}{3}\right)}, x\right), {x}^{2}\right), \varepsilon\right) \]
      10. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, \color{blue}{x \cdot \frac{4}{3}}, \frac{1}{3}\right), x\right), {x}^{2}\right), \varepsilon\right) \]
      11. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, \color{blue}{x \cdot \frac{4}{3}}, \frac{1}{3}\right), x\right), {x}^{2}\right), \varepsilon\right) \]
      12. unpow2N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, x \cdot \frac{4}{3}, \frac{1}{3}\right), x\right), \color{blue}{x \cdot x}\right), \varepsilon\right) \]
      13. *-lowering-*.f6498.9

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, x \cdot 1.3333333333333333, 0.3333333333333333\right), x\right), \color{blue}{x \cdot x}\right), \varepsilon\right) \]
    10. Simplified98.9%

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, x \cdot 1.3333333333333333, 0.3333333333333333\right), x\right), x \cdot x\right)}, \varepsilon\right) \]
    11. Add Preprocessing

    Alternative 7: 98.3% accurate, 8.0× speedup?

    \[\begin{array}{l} \\ \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, \varepsilon + x, \left(\varepsilon \cdot \varepsilon\right) \cdot 0.3333333333333333\right), \varepsilon\right) \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (fma eps (fma x (+ eps x) (* (* eps eps) 0.3333333333333333)) eps))
    double code(double x, double eps) {
    	return fma(eps, fma(x, (eps + x), ((eps * eps) * 0.3333333333333333)), eps);
    }
    
    function code(x, eps)
    	return fma(eps, fma(x, Float64(eps + x), Float64(Float64(eps * eps) * 0.3333333333333333)), eps)
    end
    
    code[x_, eps_] := N[(eps * N[(x * N[(eps + x), $MachinePrecision] + N[(N[(eps * eps), $MachinePrecision] * 0.3333333333333333), $MachinePrecision]), $MachinePrecision] + eps), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, \varepsilon + x, \left(\varepsilon \cdot \varepsilon\right) \cdot 0.3333333333333333\right), \varepsilon\right)
    \end{array}
    
    Derivation
    1. Initial program 61.3%

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

      \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x} + \left(\frac{1}{6} \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x} + \frac{\sin x \cdot \left(\frac{1}{6} + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(\frac{-1}{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + \frac{1}{6} \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)}{\cos x}\right)\right)\right) - \left(\frac{1}{6} + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(\frac{-1}{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + \frac{1}{6} \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)\right) - -1 \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
    4. Simplified99.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(0.3333333333333333, \frac{\sin x + \frac{{\sin x}^{3}}{{\cos x}^{2}}}{\cos x}, \left(\frac{{\sin x}^{2} + \frac{{\sin x}^{4}}{{\cos x}^{2}}}{{\cos x}^{2}} - \left(0.16666666666666666 + \mathsf{fma}\left(0.16666666666666666, \frac{{\sin x}^{2}}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, \frac{{\sin x}^{2}}{{\cos x}^{2}}, -0.5\right)\right)\right)\right) \cdot \frac{\sin x}{\cos x}\right), \frac{{\sin x}^{2} + \frac{{\sin x}^{4}}{{\cos x}^{2}}}{{\cos x}^{2}} - \left(0.16666666666666666 + \mathsf{fma}\left(0.16666666666666666, \frac{{\sin x}^{2}}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, \frac{{\sin x}^{2}}{{\cos x}^{2}}, -0.5\right)\right)\right)\right), \frac{\sin x + \frac{{\sin x}^{3}}{{\cos x}^{2}}}{\cos x}\right), \frac{{\sin x}^{2}}{{\cos x}^{2}}\right), \varepsilon\right)} \]
    5. Taylor expanded in x around 0

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\frac{1}{3} \cdot {\varepsilon}^{2} + x \cdot \left(\varepsilon \cdot \left(1 + \frac{2}{3} \cdot {\varepsilon}^{2}\right) + x \cdot \left(1 + \frac{4}{3} \cdot {\varepsilon}^{2}\right)\right)}, \varepsilon\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{x \cdot \left(\varepsilon \cdot \left(1 + \frac{2}{3} \cdot {\varepsilon}^{2}\right) + x \cdot \left(1 + \frac{4}{3} \cdot {\varepsilon}^{2}\right)\right) + \frac{1}{3} \cdot {\varepsilon}^{2}}, \varepsilon\right) \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(x, \varepsilon \cdot \left(1 + \frac{2}{3} \cdot {\varepsilon}^{2}\right) + x \cdot \left(1 + \frac{4}{3} \cdot {\varepsilon}^{2}\right), \frac{1}{3} \cdot {\varepsilon}^{2}\right)}, \varepsilon\right) \]
    7. Simplified98.9%

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 1.3333333333333333, 1\right), \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.6666666666666666, 1\right)\right), 0.3333333333333333 \cdot \left(\varepsilon \cdot \varepsilon\right)\right)}, \varepsilon\right) \]
    8. Taylor expanded in eps around 0

      \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, \color{blue}{\varepsilon + x}, \frac{1}{3} \cdot \left(\varepsilon \cdot \varepsilon\right)\right), \varepsilon\right) \]
    9. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, \color{blue}{x + \varepsilon}, \frac{1}{3} \cdot \left(\varepsilon \cdot \varepsilon\right)\right), \varepsilon\right) \]
      2. +-lowering-+.f6498.9

        \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, \color{blue}{x + \varepsilon}, 0.3333333333333333 \cdot \left(\varepsilon \cdot \varepsilon\right)\right), \varepsilon\right) \]
    10. Simplified98.9%

      \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, \color{blue}{x + \varepsilon}, 0.3333333333333333 \cdot \left(\varepsilon \cdot \varepsilon\right)\right), \varepsilon\right) \]
    11. Final simplification98.9%

      \[\leadsto \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(x, \varepsilon + x, \left(\varepsilon \cdot \varepsilon\right) \cdot 0.3333333333333333\right), \varepsilon\right) \]
    12. Add Preprocessing

    Alternative 8: 98.2% accurate, 13.8× speedup?

    \[\begin{array}{l} \\ \mathsf{fma}\left(\varepsilon, x \cdot \left(\varepsilon + x\right), \varepsilon\right) \end{array} \]
    (FPCore (x eps) :precision binary64 (fma eps (* x (+ eps x)) eps))
    double code(double x, double eps) {
    	return fma(eps, (x * (eps + x)), eps);
    }
    
    function code(x, eps)
    	return fma(eps, Float64(x * Float64(eps + x)), eps)
    end
    
    code[x_, eps_] := N[(eps * N[(x * N[(eps + x), $MachinePrecision]), $MachinePrecision] + eps), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{fma}\left(\varepsilon, x \cdot \left(\varepsilon + x\right), \varepsilon\right)
    \end{array}
    
    Derivation
    1. Initial program 61.3%

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

      \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x} + \left(\frac{1}{6} \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x} + \frac{\sin x \cdot \left(\frac{1}{6} + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(\frac{-1}{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + \frac{1}{6} \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)}{\cos x}\right)\right)\right) - \left(\frac{1}{6} + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(\frac{-1}{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + \frac{1}{6} \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)\right) - -1 \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
    4. Simplified99.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(0.3333333333333333, \frac{\sin x + \frac{{\sin x}^{3}}{{\cos x}^{2}}}{\cos x}, \left(\frac{{\sin x}^{2} + \frac{{\sin x}^{4}}{{\cos x}^{2}}}{{\cos x}^{2}} - \left(0.16666666666666666 + \mathsf{fma}\left(0.16666666666666666, \frac{{\sin x}^{2}}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, \frac{{\sin x}^{2}}{{\cos x}^{2}}, -0.5\right)\right)\right)\right) \cdot \frac{\sin x}{\cos x}\right), \frac{{\sin x}^{2} + \frac{{\sin x}^{4}}{{\cos x}^{2}}}{{\cos x}^{2}} - \left(0.16666666666666666 + \mathsf{fma}\left(0.16666666666666666, \frac{{\sin x}^{2}}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, \frac{{\sin x}^{2}}{{\cos x}^{2}}, -0.5\right)\right)\right)\right), \frac{\sin x + \frac{{\sin x}^{3}}{{\cos x}^{2}}}{\cos x}\right), \frac{{\sin x}^{2}}{{\cos x}^{2}}\right), \varepsilon\right)} \]
    5. Taylor expanded in x around 0

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\frac{1}{3} \cdot {\varepsilon}^{2} + x \cdot \left(\varepsilon \cdot \left(1 + \frac{2}{3} \cdot {\varepsilon}^{2}\right) + x \cdot \left(1 + \frac{4}{3} \cdot {\varepsilon}^{2}\right)\right)}, \varepsilon\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{x \cdot \left(\varepsilon \cdot \left(1 + \frac{2}{3} \cdot {\varepsilon}^{2}\right) + x \cdot \left(1 + \frac{4}{3} \cdot {\varepsilon}^{2}\right)\right) + \frac{1}{3} \cdot {\varepsilon}^{2}}, \varepsilon\right) \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(x, \varepsilon \cdot \left(1 + \frac{2}{3} \cdot {\varepsilon}^{2}\right) + x \cdot \left(1 + \frac{4}{3} \cdot {\varepsilon}^{2}\right), \frac{1}{3} \cdot {\varepsilon}^{2}\right)}, \varepsilon\right) \]
    7. Simplified98.9%

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 1.3333333333333333, 1\right), \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.6666666666666666, 1\right)\right), 0.3333333333333333 \cdot \left(\varepsilon \cdot \varepsilon\right)\right)}, \varepsilon\right) \]
    8. Taylor expanded in eps around 0

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\varepsilon \cdot x + {x}^{2}}, \varepsilon\right) \]
    9. Step-by-step derivation
      1. unpow2N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \varepsilon \cdot x + \color{blue}{x \cdot x}, \varepsilon\right) \]
      2. distribute-rgt-outN/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{x \cdot \left(\varepsilon + x\right)}, \varepsilon\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{x \cdot \left(\varepsilon + x\right)}, \varepsilon\right) \]
      4. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, x \cdot \color{blue}{\left(x + \varepsilon\right)}, \varepsilon\right) \]
      5. +-lowering-+.f6498.9

        \[\leadsto \mathsf{fma}\left(\varepsilon, x \cdot \color{blue}{\left(x + \varepsilon\right)}, \varepsilon\right) \]
    10. Simplified98.9%

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{x \cdot \left(x + \varepsilon\right)}, \varepsilon\right) \]
    11. Final simplification98.9%

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

    Alternative 9: 98.2% accurate, 17.3× speedup?

    \[\begin{array}{l} \\ \mathsf{fma}\left(\varepsilon, x \cdot x, \varepsilon\right) \end{array} \]
    (FPCore (x eps) :precision binary64 (fma eps (* x x) eps))
    double code(double x, double eps) {
    	return fma(eps, (x * x), eps);
    }
    
    function code(x, eps)
    	return fma(eps, Float64(x * x), eps)
    end
    
    code[x_, eps_] := N[(eps * N[(x * x), $MachinePrecision] + eps), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{fma}\left(\varepsilon, x \cdot x, \varepsilon\right)
    \end{array}
    
    Derivation
    1. Initial program 61.3%

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

      \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x} + \left(\frac{1}{6} \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x} + \frac{\sin x \cdot \left(\frac{1}{6} + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(\frac{-1}{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + \frac{1}{6} \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)}{\cos x}\right)\right)\right) - \left(\frac{1}{6} + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(\frac{-1}{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + \frac{1}{6} \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)\right) - -1 \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
    4. Simplified99.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(0.3333333333333333, \frac{\sin x + \frac{{\sin x}^{3}}{{\cos x}^{2}}}{\cos x}, \left(\frac{{\sin x}^{2} + \frac{{\sin x}^{4}}{{\cos x}^{2}}}{{\cos x}^{2}} - \left(0.16666666666666666 + \mathsf{fma}\left(0.16666666666666666, \frac{{\sin x}^{2}}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, \frac{{\sin x}^{2}}{{\cos x}^{2}}, -0.5\right)\right)\right)\right) \cdot \frac{\sin x}{\cos x}\right), \frac{{\sin x}^{2} + \frac{{\sin x}^{4}}{{\cos x}^{2}}}{{\cos x}^{2}} - \left(0.16666666666666666 + \mathsf{fma}\left(0.16666666666666666, \frac{{\sin x}^{2}}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, \frac{{\sin x}^{2}}{{\cos x}^{2}}, -0.5\right)\right)\right)\right), \frac{\sin x + \frac{{\sin x}^{3}}{{\cos x}^{2}}}{\cos x}\right), \frac{{\sin x}^{2}}{{\cos x}^{2}}\right), \varepsilon\right)} \]
    5. Taylor expanded in x around 0

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\frac{1}{3} \cdot {\varepsilon}^{2} + x \cdot \left(\varepsilon \cdot \left(1 + \frac{2}{3} \cdot {\varepsilon}^{2}\right) + x \cdot \left(1 + \frac{4}{3} \cdot {\varepsilon}^{2}\right)\right)}, \varepsilon\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{x \cdot \left(\varepsilon \cdot \left(1 + \frac{2}{3} \cdot {\varepsilon}^{2}\right) + x \cdot \left(1 + \frac{4}{3} \cdot {\varepsilon}^{2}\right)\right) + \frac{1}{3} \cdot {\varepsilon}^{2}}, \varepsilon\right) \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(x, \varepsilon \cdot \left(1 + \frac{2}{3} \cdot {\varepsilon}^{2}\right) + x \cdot \left(1 + \frac{4}{3} \cdot {\varepsilon}^{2}\right), \frac{1}{3} \cdot {\varepsilon}^{2}\right)}, \varepsilon\right) \]
    7. Simplified98.9%

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 1.3333333333333333, 1\right), \varepsilon \cdot \mathsf{fma}\left(\varepsilon, \varepsilon \cdot 0.6666666666666666, 1\right)\right), 0.3333333333333333 \cdot \left(\varepsilon \cdot \varepsilon\right)\right)}, \varepsilon\right) \]
    8. Taylor expanded in eps around 0

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{{x}^{2}}, \varepsilon\right) \]
    9. Step-by-step derivation
      1. unpow2N/A

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{x \cdot x}, \varepsilon\right) \]
      2. *-lowering-*.f6498.9

        \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{x \cdot x}, \varepsilon\right) \]
    10. Simplified98.9%

      \[\leadsto \mathsf{fma}\left(\varepsilon, \color{blue}{x \cdot x}, \varepsilon\right) \]
    11. 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;
    }
    
    real(8) function code(x, eps)
        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 61.3%

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

      \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \varepsilon}} \]
    4. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \varepsilon}} \]
      2. sin-lowering-sin.f64N/A

        \[\leadsto \frac{\color{blue}{\sin \varepsilon}}{\cos \varepsilon} \]
      3. cos-lowering-cos.f6498.4

        \[\leadsto \frac{\sin \varepsilon}{\color{blue}{\cos \varepsilon}} \]
    5. Simplified98.4%

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

      \[\leadsto \color{blue}{\varepsilon} \]
    7. Step-by-step derivation
      1. Simplified98.4%

        \[\leadsto \color{blue}{\varepsilon} \]
      2. Add Preprocessing

      Developer Target 1: 99.9% accurate, 0.6× speedup?

      \[\begin{array}{l} \\ \frac{\sin \varepsilon}{\cos x \cdot \cos \left(x + \varepsilon\right)} \end{array} \]
      (FPCore (x eps) :precision binary64 (/ (sin eps) (* (cos x) (cos (+ x eps)))))
      double code(double x, double eps) {
      	return sin(eps) / (cos(x) * cos((x + eps)));
      }
      
      real(8) function code(x, eps)
          real(8), intent (in) :: x
          real(8), intent (in) :: eps
          code = sin(eps) / (cos(x) * cos((x + eps)))
      end function
      
      public static double code(double x, double eps) {
      	return Math.sin(eps) / (Math.cos(x) * Math.cos((x + eps)));
      }
      
      def code(x, eps):
      	return math.sin(eps) / (math.cos(x) * math.cos((x + eps)))
      
      function code(x, eps)
      	return Float64(sin(eps) / Float64(cos(x) * cos(Float64(x + eps))))
      end
      
      function tmp = code(x, eps)
      	tmp = sin(eps) / (cos(x) * cos((x + eps)));
      end
      
      code[x_, eps_] := N[(N[Sin[eps], $MachinePrecision] / N[(N[Cos[x], $MachinePrecision] * N[Cos[N[(x + eps), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{\sin \varepsilon}{\cos x \cdot \cos \left(x + \varepsilon\right)}
      \end{array}
      

      Developer Target 2: 62.6% accurate, 0.4× speedup?

      \[\begin{array}{l} \\ \frac{\tan x + \tan \varepsilon}{1 - \tan x \cdot \tan \varepsilon} - \tan x \end{array} \]
      (FPCore (x eps)
       :precision binary64
       (- (/ (+ (tan x) (tan eps)) (- 1.0 (* (tan x) (tan eps)))) (tan x)))
      double code(double x, double eps) {
      	return ((tan(x) + tan(eps)) / (1.0 - (tan(x) * tan(eps)))) - tan(x);
      }
      
      real(8) function code(x, eps)
          real(8), intent (in) :: x
          real(8), intent (in) :: eps
          code = ((tan(x) + tan(eps)) / (1.0d0 - (tan(x) * tan(eps)))) - tan(x)
      end function
      
      public static double code(double x, double eps) {
      	return ((Math.tan(x) + Math.tan(eps)) / (1.0 - (Math.tan(x) * Math.tan(eps)))) - Math.tan(x);
      }
      
      def code(x, eps):
      	return ((math.tan(x) + math.tan(eps)) / (1.0 - (math.tan(x) * math.tan(eps)))) - math.tan(x)
      
      function code(x, eps)
      	return Float64(Float64(Float64(tan(x) + tan(eps)) / Float64(1.0 - Float64(tan(x) * tan(eps)))) - tan(x))
      end
      
      function tmp = code(x, eps)
      	tmp = ((tan(x) + tan(eps)) / (1.0 - (tan(x) * tan(eps)))) - tan(x);
      end
      
      code[x_, eps_] := N[(N[(N[(N[Tan[x], $MachinePrecision] + N[Tan[eps], $MachinePrecision]), $MachinePrecision] / N[(1.0 - N[(N[Tan[x], $MachinePrecision] * N[Tan[eps], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Tan[x], $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{\tan x + \tan \varepsilon}{1 - \tan x \cdot \tan \varepsilon} - \tan x
      \end{array}
      

      Developer Target 3: 98.9% 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));
      }
      
      real(8) function code(x, eps)
          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 2024198 
      (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 (/ (sin eps) (* (cos x) (cos (+ x eps)))))
      
        :alt
        (! :herbie-platform default (- (/ (+ (tan x) (tan eps)) (- 1 (* (tan x) (tan eps)))) (tan x)))
      
        :alt
        (! :herbie-platform default (+ eps (* eps (tan x) (tan x))))
      
        (- (tan (+ x eps)) (tan x)))