expfmod (used to be hard to sample)

Percentage Accurate: 7.2% → 62.0%
Time: 12.3s
Alternatives: 6
Speedup: 2.0×

Specification

?
\[\begin{array}{l} \\ \left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \end{array} \]
(FPCore (x) :precision binary64 (* (fmod (exp x) (sqrt (cos x))) (exp (- x))))
double code(double x) {
	return fmod(exp(x), sqrt(cos(x))) * exp(-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)
use fmin_fmax_functions
    real(8), intent (in) :: x
    code = mod(exp(x), sqrt(cos(x))) * exp(-x)
end function
def code(x):
	return math.fmod(math.exp(x), math.sqrt(math.cos(x))) * math.exp(-x)
function code(x)
	return Float64(rem(exp(x), sqrt(cos(x))) * exp(Float64(-x)))
end
code[x_] := N[(N[With[{TMP1 = N[Exp[x], $MachinePrecision], TMP2 = N[Sqrt[N[Cos[x], $MachinePrecision]], $MachinePrecision]}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-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 6 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: 7.2% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \end{array} \]
(FPCore (x) :precision binary64 (* (fmod (exp x) (sqrt (cos x))) (exp (- x))))
double code(double x) {
	return fmod(exp(x), sqrt(cos(x))) * exp(-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)
use fmin_fmax_functions
    real(8), intent (in) :: x
    code = mod(exp(x), sqrt(cos(x))) * exp(-x)
end function
def code(x):
	return math.fmod(math.exp(x), math.sqrt(math.cos(x))) * math.exp(-x)
function code(x)
	return Float64(rem(exp(x), sqrt(cos(x))) * exp(Float64(-x)))
end
code[x_] := N[(N[With[{TMP1 = N[Exp[x], $MachinePrecision], TMP2 = N[Sqrt[N[Cos[x], $MachinePrecision]], $MachinePrecision]}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x}
\end{array}

Alternative 1: 62.0% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -5 \cdot 10^{-310}:\\ \;\;\;\;\left(\left(e^{x}\right) \bmod \left(\mathsf{fma}\left(\mathsf{fma}\left(-0.010416666666666666, x \cdot x, -0.25\right), x \cdot x, 1\right)\right)\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666, x, 0.5\right), x \cdot x, \frac{1 - x \cdot x}{1 + x}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(x \bmod 1\right) \cdot e^{-x}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -5e-310)
   (*
    (fmod (exp x) (fma (fma -0.010416666666666666 (* x x) -0.25) (* x x) 1.0))
    (fma
     (fma -0.16666666666666666 x 0.5)
     (* x x)
     (/ (- 1.0 (* x x)) (+ 1.0 x))))
   (* (fmod x 1.0) (exp (- x)))))
double code(double x) {
	double tmp;
	if (x <= -5e-310) {
		tmp = fmod(exp(x), fma(fma(-0.010416666666666666, (x * x), -0.25), (x * x), 1.0)) * fma(fma(-0.16666666666666666, x, 0.5), (x * x), ((1.0 - (x * x)) / (1.0 + x)));
	} else {
		tmp = fmod(x, 1.0) * exp(-x);
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= -5e-310)
		tmp = Float64(rem(exp(x), fma(fma(-0.010416666666666666, Float64(x * x), -0.25), Float64(x * x), 1.0)) * fma(fma(-0.16666666666666666, x, 0.5), Float64(x * x), Float64(Float64(1.0 - Float64(x * x)) / Float64(1.0 + x))));
	else
		tmp = Float64(rem(x, 1.0) * exp(Float64(-x)));
	end
	return tmp
end
code[x_] := If[LessEqual[x, -5e-310], N[(N[With[{TMP1 = N[Exp[x], $MachinePrecision], TMP2 = N[(N[(-0.010416666666666666 * N[(x * x), $MachinePrecision] + -0.25), $MachinePrecision] * N[(x * x), $MachinePrecision] + 1.0), $MachinePrecision]}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * N[(N[(-0.16666666666666666 * x + 0.5), $MachinePrecision] * N[(x * x), $MachinePrecision] + N[(N[(1.0 - N[(x * x), $MachinePrecision]), $MachinePrecision] / N[(1.0 + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[With[{TMP1 = x, TMP2 = 1.0}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -5 \cdot 10^{-310}:\\
\;\;\;\;\left(\left(e^{x}\right) \bmod \left(\mathsf{fma}\left(\mathsf{fma}\left(-0.010416666666666666, x \cdot x, -0.25\right), x \cdot x, 1\right)\right)\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666, x, 0.5\right), x \cdot x, \frac{1 - x \cdot x}{1 + x}\right)\\

\mathbf{else}:\\
\;\;\;\;\left(x \bmod 1\right) \cdot e^{-x}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -4.999999999999985e-310

    1. Initial program 8.1%

      \[\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{x \cdot \left(-1 \cdot \left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) + x \cdot \left(\frac{-1}{6} \cdot \left(x \cdot \left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right)\right) + \frac{1}{2} \cdot \left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right)\right)\right) + \left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right)} \]
    4. Applied rewrites8.2%

      \[\leadsto \color{blue}{\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666, x, 0.5\right), x \cdot x, 1 - x\right)} \]
    5. Taylor expanded in x around 0

      \[\leadsto \left(\left(e^{x}\right) \bmod \left(1 + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-19}{5760} \cdot {x}^{2} - \frac{1}{96}\right) - \frac{1}{4}\right)\right)\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\frac{-1}{6}, \color{blue}{x}, \frac{1}{2}\right), x \cdot x, 1 - x\right) \]
    6. Step-by-step derivation
      1. Applied rewrites8.2%

        \[\leadsto \left(\left(e^{x}\right) \bmod \left(\mathsf{fma}\left(\left(\left(-0.003298611111111111 \cdot \left(x \cdot x\right) - 0.010416666666666666\right) \cdot x\right) \cdot x - 0.25, x \cdot x, 1\right)\right)\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666, \color{blue}{x}, 0.5\right), x \cdot x, 1 - x\right) \]
      2. Taylor expanded in x around 0

        \[\leadsto \left(\left(e^{x}\right) \bmod \left(1 + {x}^{2} \cdot \left(\frac{-1}{96} \cdot {x}^{2} - \frac{1}{4}\right)\right)\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\frac{-1}{6}, x, \frac{1}{2}\right), x \cdot x, 1 - x\right) \]
      3. Step-by-step derivation
        1. Applied rewrites8.2%

          \[\leadsto \left(\left(e^{x}\right) \bmod \left(\mathsf{fma}\left(\mathsf{fma}\left(-0.010416666666666666, x \cdot x, -0.25\right), x \cdot x, 1\right)\right)\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666, x, 0.5\right), x \cdot x, 1 - x\right) \]
        2. Step-by-step derivation
          1. Applied rewrites8.2%

            \[\leadsto \left(\left(e^{x}\right) \bmod \left(\mathsf{fma}\left(\mathsf{fma}\left(-0.010416666666666666, x \cdot x, -0.25\right), x \cdot x, 1\right)\right)\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666, x, 0.5\right), x \cdot x, \frac{1 - x \cdot x}{1 + x}\right) \]

          if -4.999999999999985e-310 < x

          1. Initial program 6.6%

            \[\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
          4. Step-by-step derivation
            1. Applied rewrites38.8%

              \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
            2. Taylor expanded in x around 0

              \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
            3. Step-by-step derivation
              1. Applied rewrites38.5%

                \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
              2. Taylor expanded in x around 0

                \[\leadsto \left(\color{blue}{\left(1 + x\right)} \bmod 1\right) \cdot e^{-x} \]
              3. Step-by-step derivation
                1. Applied rewrites40.2%

                  \[\leadsto \left(\color{blue}{\left(x - -1\right)} \bmod 1\right) \cdot e^{-x} \]
                2. Taylor expanded in x around inf

                  \[\leadsto \left(x \bmod 1\right) \cdot e^{-x} \]
                3. Step-by-step derivation
                  1. Applied rewrites97.8%

                    \[\leadsto \left(x \bmod 1\right) \cdot e^{-x} \]
                4. Recombined 2 regimes into one program.
                5. Add Preprocessing

                Alternative 2: 62.0% accurate, 1.8× speedup?

                \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -5 \cdot 10^{-310}:\\ \;\;\;\;\left(\left(e^{x}\right) \bmod 1\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666, x, 0.5\right), x \cdot x, 1 - x\right)\\ \mathbf{else}:\\ \;\;\;\;\left(x \bmod 1\right) \cdot e^{-x}\\ \end{array} \end{array} \]
                (FPCore (x)
                 :precision binary64
                 (if (<= x -5e-310)
                   (*
                    (fmod (exp x) 1.0)
                    (fma (fma -0.16666666666666666 x 0.5) (* x x) (- 1.0 x)))
                   (* (fmod x 1.0) (exp (- x)))))
                double code(double x) {
                	double tmp;
                	if (x <= -5e-310) {
                		tmp = fmod(exp(x), 1.0) * fma(fma(-0.16666666666666666, x, 0.5), (x * x), (1.0 - x));
                	} else {
                		tmp = fmod(x, 1.0) * exp(-x);
                	}
                	return tmp;
                }
                
                function code(x)
                	tmp = 0.0
                	if (x <= -5e-310)
                		tmp = Float64(rem(exp(x), 1.0) * fma(fma(-0.16666666666666666, x, 0.5), Float64(x * x), Float64(1.0 - x)));
                	else
                		tmp = Float64(rem(x, 1.0) * exp(Float64(-x)));
                	end
                	return tmp
                end
                
                code[x_] := If[LessEqual[x, -5e-310], N[(N[With[{TMP1 = N[Exp[x], $MachinePrecision], TMP2 = 1.0}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * N[(N[(-0.16666666666666666 * x + 0.5), $MachinePrecision] * N[(x * x), $MachinePrecision] + N[(1.0 - x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[With[{TMP1 = x, TMP2 = 1.0}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]]
                
                \begin{array}{l}
                
                \\
                \begin{array}{l}
                \mathbf{if}\;x \leq -5 \cdot 10^{-310}:\\
                \;\;\;\;\left(\left(e^{x}\right) \bmod 1\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666, x, 0.5\right), x \cdot x, 1 - x\right)\\
                
                \mathbf{else}:\\
                \;\;\;\;\left(x \bmod 1\right) \cdot e^{-x}\\
                
                
                \end{array}
                \end{array}
                
                Derivation
                1. Split input into 2 regimes
                2. if x < -4.999999999999985e-310

                  1. Initial program 8.1%

                    \[\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                  2. Add Preprocessing
                  3. Taylor expanded in x around 0

                    \[\leadsto \color{blue}{x \cdot \left(-1 \cdot \left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) + x \cdot \left(\frac{-1}{6} \cdot \left(x \cdot \left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right)\right) + \frac{1}{2} \cdot \left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right)\right)\right) + \left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right)} \]
                  4. Applied rewrites8.2%

                    \[\leadsto \color{blue}{\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666, x, 0.5\right), x \cdot x, 1 - x\right)} \]
                  5. Taylor expanded in x around 0

                    \[\leadsto \left(\left(e^{x}\right) \bmod 1\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\frac{-1}{6}, \color{blue}{x}, \frac{1}{2}\right), x \cdot x, 1 - x\right) \]
                  6. Step-by-step derivation
                    1. Applied rewrites8.2%

                      \[\leadsto \left(\left(e^{x}\right) \bmod 1\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666, \color{blue}{x}, 0.5\right), x \cdot x, 1 - x\right) \]

                    if -4.999999999999985e-310 < x

                    1. Initial program 6.6%

                      \[\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                    2. Add Preprocessing
                    3. Taylor expanded in x around 0

                      \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                    4. Step-by-step derivation
                      1. Applied rewrites38.8%

                        \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                      2. Taylor expanded in x around 0

                        \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                      3. Step-by-step derivation
                        1. Applied rewrites38.5%

                          \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                        2. Taylor expanded in x around 0

                          \[\leadsto \left(\color{blue}{\left(1 + x\right)} \bmod 1\right) \cdot e^{-x} \]
                        3. Step-by-step derivation
                          1. Applied rewrites40.2%

                            \[\leadsto \left(\color{blue}{\left(x - -1\right)} \bmod 1\right) \cdot e^{-x} \]
                          2. Taylor expanded in x around inf

                            \[\leadsto \left(x \bmod 1\right) \cdot e^{-x} \]
                          3. Step-by-step derivation
                            1. Applied rewrites97.8%

                              \[\leadsto \left(x \bmod 1\right) \cdot e^{-x} \]
                          4. Recombined 2 regimes into one program.
                          5. Add Preprocessing

                          Alternative 3: 61.9% accurate, 1.8× speedup?

                          \[\begin{array}{l} \\ \begin{array}{l} t_0 := e^{-x}\\ \mathbf{if}\;x \leq -5 \cdot 10^{-310}:\\ \;\;\;\;\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.5, x, 1\right), x, 1\right)\right) \bmod 1\right) \cdot t\_0\\ \mathbf{else}:\\ \;\;\;\;\left(x \bmod 1\right) \cdot t\_0\\ \end{array} \end{array} \]
                          (FPCore (x)
                           :precision binary64
                           (let* ((t_0 (exp (- x))))
                             (if (<= x -5e-310)
                               (* (fmod (fma (fma 0.5 x 1.0) x 1.0) 1.0) t_0)
                               (* (fmod x 1.0) t_0))))
                          double code(double x) {
                          	double t_0 = exp(-x);
                          	double tmp;
                          	if (x <= -5e-310) {
                          		tmp = fmod(fma(fma(0.5, x, 1.0), x, 1.0), 1.0) * t_0;
                          	} else {
                          		tmp = fmod(x, 1.0) * t_0;
                          	}
                          	return tmp;
                          }
                          
                          function code(x)
                          	t_0 = exp(Float64(-x))
                          	tmp = 0.0
                          	if (x <= -5e-310)
                          		tmp = Float64(rem(fma(fma(0.5, x, 1.0), x, 1.0), 1.0) * t_0);
                          	else
                          		tmp = Float64(rem(x, 1.0) * t_0);
                          	end
                          	return tmp
                          end
                          
                          code[x_] := Block[{t$95$0 = N[Exp[(-x)], $MachinePrecision]}, If[LessEqual[x, -5e-310], N[(N[With[{TMP1 = N[(N[(0.5 * x + 1.0), $MachinePrecision] * x + 1.0), $MachinePrecision], TMP2 = 1.0}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * t$95$0), $MachinePrecision], N[(N[With[{TMP1 = x, TMP2 = 1.0}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * t$95$0), $MachinePrecision]]]
                          
                          \begin{array}{l}
                          
                          \\
                          \begin{array}{l}
                          t_0 := e^{-x}\\
                          \mathbf{if}\;x \leq -5 \cdot 10^{-310}:\\
                          \;\;\;\;\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.5, x, 1\right), x, 1\right)\right) \bmod 1\right) \cdot t\_0\\
                          
                          \mathbf{else}:\\
                          \;\;\;\;\left(x \bmod 1\right) \cdot t\_0\\
                          
                          
                          \end{array}
                          \end{array}
                          
                          Derivation
                          1. Split input into 2 regimes
                          2. if x < -4.999999999999985e-310

                            1. Initial program 8.1%

                              \[\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                            2. Add Preprocessing
                            3. Taylor expanded in x around 0

                              \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                            4. Step-by-step derivation
                              1. Applied rewrites3.4%

                                \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                              2. Taylor expanded in x around 0

                                \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                              3. Step-by-step derivation
                                1. Applied rewrites3.1%

                                  \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                                2. Taylor expanded in x around 0

                                  \[\leadsto \left(\color{blue}{\left(1 + x \cdot \left(1 + \frac{1}{2} \cdot x\right)\right)} \bmod 1\right) \cdot e^{-x} \]
                                3. Step-by-step derivation
                                  1. Applied rewrites8.0%

                                    \[\leadsto \left(\color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(0.5, x, 1\right), x, 1\right)\right)} \bmod 1\right) \cdot e^{-x} \]

                                  if -4.999999999999985e-310 < x

                                  1. Initial program 6.6%

                                    \[\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                  2. Add Preprocessing
                                  3. Taylor expanded in x around 0

                                    \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                  4. Step-by-step derivation
                                    1. Applied rewrites38.8%

                                      \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                    2. Taylor expanded in x around 0

                                      \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                                    3. Step-by-step derivation
                                      1. Applied rewrites38.5%

                                        \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                                      2. Taylor expanded in x around 0

                                        \[\leadsto \left(\color{blue}{\left(1 + x\right)} \bmod 1\right) \cdot e^{-x} \]
                                      3. Step-by-step derivation
                                        1. Applied rewrites40.2%

                                          \[\leadsto \left(\color{blue}{\left(x - -1\right)} \bmod 1\right) \cdot e^{-x} \]
                                        2. Taylor expanded in x around inf

                                          \[\leadsto \left(x \bmod 1\right) \cdot e^{-x} \]
                                        3. Step-by-step derivation
                                          1. Applied rewrites97.8%

                                            \[\leadsto \left(x \bmod 1\right) \cdot e^{-x} \]
                                        4. Recombined 2 regimes into one program.
                                        5. Add Preprocessing

                                        Alternative 4: 61.8% accurate, 1.9× speedup?

                                        \[\begin{array}{l} \\ \begin{array}{l} t_0 := e^{-x}\\ \mathbf{if}\;x \leq -5 \cdot 10^{-310}:\\ \;\;\;\;\left(\left(x - -1\right) \bmod 1\right) \cdot t\_0\\ \mathbf{else}:\\ \;\;\;\;\left(x \bmod 1\right) \cdot t\_0\\ \end{array} \end{array} \]
                                        (FPCore (x)
                                         :precision binary64
                                         (let* ((t_0 (exp (- x))))
                                           (if (<= x -5e-310) (* (fmod (- x -1.0) 1.0) t_0) (* (fmod x 1.0) t_0))))
                                        double code(double x) {
                                        	double t_0 = exp(-x);
                                        	double tmp;
                                        	if (x <= -5e-310) {
                                        		tmp = fmod((x - -1.0), 1.0) * t_0;
                                        	} else {
                                        		tmp = fmod(x, 1.0) * t_0;
                                        	}
                                        	return tmp;
                                        }
                                        
                                        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)
                                        use fmin_fmax_functions
                                            real(8), intent (in) :: x
                                            real(8) :: t_0
                                            real(8) :: tmp
                                            t_0 = exp(-x)
                                            if (x <= (-5d-310)) then
                                                tmp = mod((x - (-1.0d0)), 1.0d0) * t_0
                                            else
                                                tmp = mod(x, 1.0d0) * t_0
                                            end if
                                            code = tmp
                                        end function
                                        
                                        def code(x):
                                        	t_0 = math.exp(-x)
                                        	tmp = 0
                                        	if x <= -5e-310:
                                        		tmp = math.fmod((x - -1.0), 1.0) * t_0
                                        	else:
                                        		tmp = math.fmod(x, 1.0) * t_0
                                        	return tmp
                                        
                                        function code(x)
                                        	t_0 = exp(Float64(-x))
                                        	tmp = 0.0
                                        	if (x <= -5e-310)
                                        		tmp = Float64(rem(Float64(x - -1.0), 1.0) * t_0);
                                        	else
                                        		tmp = Float64(rem(x, 1.0) * t_0);
                                        	end
                                        	return tmp
                                        end
                                        
                                        code[x_] := Block[{t$95$0 = N[Exp[(-x)], $MachinePrecision]}, If[LessEqual[x, -5e-310], N[(N[With[{TMP1 = N[(x - -1.0), $MachinePrecision], TMP2 = 1.0}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * t$95$0), $MachinePrecision], N[(N[With[{TMP1 = x, TMP2 = 1.0}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * t$95$0), $MachinePrecision]]]
                                        
                                        \begin{array}{l}
                                        
                                        \\
                                        \begin{array}{l}
                                        t_0 := e^{-x}\\
                                        \mathbf{if}\;x \leq -5 \cdot 10^{-310}:\\
                                        \;\;\;\;\left(\left(x - -1\right) \bmod 1\right) \cdot t\_0\\
                                        
                                        \mathbf{else}:\\
                                        \;\;\;\;\left(x \bmod 1\right) \cdot t\_0\\
                                        
                                        
                                        \end{array}
                                        \end{array}
                                        
                                        Derivation
                                        1. Split input into 2 regimes
                                        2. if x < -4.999999999999985e-310

                                          1. Initial program 8.1%

                                            \[\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                          2. Add Preprocessing
                                          3. Taylor expanded in x around 0

                                            \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                          4. Step-by-step derivation
                                            1. Applied rewrites3.4%

                                              \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                            2. Taylor expanded in x around 0

                                              \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                                            3. Step-by-step derivation
                                              1. Applied rewrites3.1%

                                                \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                                              2. Taylor expanded in x around 0

                                                \[\leadsto \left(\color{blue}{\left(1 + x\right)} \bmod 1\right) \cdot e^{-x} \]
                                              3. Step-by-step derivation
                                                1. Applied rewrites7.4%

                                                  \[\leadsto \left(\color{blue}{\left(x - -1\right)} \bmod 1\right) \cdot e^{-x} \]

                                                if -4.999999999999985e-310 < x

                                                1. Initial program 6.6%

                                                  \[\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                                2. Add Preprocessing
                                                3. Taylor expanded in x around 0

                                                  \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                                4. Step-by-step derivation
                                                  1. Applied rewrites38.8%

                                                    \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                                  2. Taylor expanded in x around 0

                                                    \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                                                  3. Step-by-step derivation
                                                    1. Applied rewrites38.5%

                                                      \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                                                    2. Taylor expanded in x around 0

                                                      \[\leadsto \left(\color{blue}{\left(1 + x\right)} \bmod 1\right) \cdot e^{-x} \]
                                                    3. Step-by-step derivation
                                                      1. Applied rewrites40.2%

                                                        \[\leadsto \left(\color{blue}{\left(x - -1\right)} \bmod 1\right) \cdot e^{-x} \]
                                                      2. Taylor expanded in x around inf

                                                        \[\leadsto \left(x \bmod 1\right) \cdot e^{-x} \]
                                                      3. Step-by-step derivation
                                                        1. Applied rewrites97.8%

                                                          \[\leadsto \left(x \bmod 1\right) \cdot e^{-x} \]
                                                      4. Recombined 2 regimes into one program.
                                                      5. Add Preprocessing

                                                      Alternative 5: 59.6% accurate, 2.0× speedup?

                                                      \[\begin{array}{l} \\ \left(x \bmod 1\right) \cdot e^{-x} \end{array} \]
                                                      (FPCore (x) :precision binary64 (* (fmod x 1.0) (exp (- x))))
                                                      double code(double x) {
                                                      	return fmod(x, 1.0) * exp(-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)
                                                      use fmin_fmax_functions
                                                          real(8), intent (in) :: x
                                                          code = mod(x, 1.0d0) * exp(-x)
                                                      end function
                                                      
                                                      def code(x):
                                                      	return math.fmod(x, 1.0) * math.exp(-x)
                                                      
                                                      function code(x)
                                                      	return Float64(rem(x, 1.0) * exp(Float64(-x)))
                                                      end
                                                      
                                                      code[x_] := N[(N[With[{TMP1 = x, TMP2 = 1.0}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]
                                                      
                                                      \begin{array}{l}
                                                      
                                                      \\
                                                      \left(x \bmod 1\right) \cdot e^{-x}
                                                      \end{array}
                                                      
                                                      Derivation
                                                      1. Initial program 7.2%

                                                        \[\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                                      2. Add Preprocessing
                                                      3. Taylor expanded in x around 0

                                                        \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                                      4. Step-by-step derivation
                                                        1. Applied rewrites25.5%

                                                          \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                                        2. Taylor expanded in x around 0

                                                          \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                                                        3. Step-by-step derivation
                                                          1. Applied rewrites25.2%

                                                            \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                                                          2. Taylor expanded in x around 0

                                                            \[\leadsto \left(\color{blue}{\left(1 + x\right)} \bmod 1\right) \cdot e^{-x} \]
                                                          3. Step-by-step derivation
                                                            1. Applied rewrites27.9%

                                                              \[\leadsto \left(\color{blue}{\left(x - -1\right)} \bmod 1\right) \cdot e^{-x} \]
                                                            2. Taylor expanded in x around inf

                                                              \[\leadsto \left(x \bmod 1\right) \cdot e^{-x} \]
                                                            3. Step-by-step derivation
                                                              1. Applied rewrites61.9%

                                                                \[\leadsto \left(x \bmod 1\right) \cdot e^{-x} \]
                                                              2. Add Preprocessing

                                                              Alternative 6: 22.7% accurate, 2.0× speedup?

                                                              \[\begin{array}{l} \\ \left(1 \bmod 1\right) \cdot e^{-x} \end{array} \]
                                                              (FPCore (x) :precision binary64 (* (fmod 1.0 1.0) (exp (- x))))
                                                              double code(double x) {
                                                              	return fmod(1.0, 1.0) * exp(-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)
                                                              use fmin_fmax_functions
                                                                  real(8), intent (in) :: x
                                                                  code = mod(1.0d0, 1.0d0) * exp(-x)
                                                              end function
                                                              
                                                              def code(x):
                                                              	return math.fmod(1.0, 1.0) * math.exp(-x)
                                                              
                                                              function code(x)
                                                              	return Float64(rem(1.0, 1.0) * exp(Float64(-x)))
                                                              end
                                                              
                                                              code[x_] := N[(N[With[{TMP1 = 1.0, TMP2 = 1.0}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]
                                                              
                                                              \begin{array}{l}
                                                              
                                                              \\
                                                              \left(1 \bmod 1\right) \cdot e^{-x}
                                                              \end{array}
                                                              
                                                              Derivation
                                                              1. Initial program 7.2%

                                                                \[\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                                              2. Add Preprocessing
                                                              3. Taylor expanded in x around 0

                                                                \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                                              4. Step-by-step derivation
                                                                1. Applied rewrites25.5%

                                                                  \[\leadsto \left(\color{blue}{1} \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \]
                                                                2. Taylor expanded in x around 0

                                                                  \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                                                                3. Step-by-step derivation
                                                                  1. Applied rewrites25.2%

                                                                    \[\leadsto \left(1 \bmod \color{blue}{1}\right) \cdot e^{-x} \]
                                                                  2. Add Preprocessing

                                                                  Reproduce

                                                                  ?
                                                                  herbie shell --seed 2025023 
                                                                  (FPCore (x)
                                                                    :name "expfmod (used to be hard to sample)"
                                                                    :precision binary64
                                                                    (* (fmod (exp x) (sqrt (cos x))) (exp (- x))))