expfmod (used to be hard to sample)

Percentage Accurate: 7.2% → 60.7%
Time: 12.1s
Alternatives: 7
Speedup: 4.1×

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);
}
real(8) function code(x)
    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 7 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);
}
real(8) function code(x)
    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: 60.7% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := e^{-x}\\ \mathbf{if}\;\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot t\_0 \leq 0.05:\\ \;\;\;\;t\_0 \cdot \left(\left(\mathsf{fma}\left(x, x \cdot 0.5, x\right)\right) \bmod 1\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(\left(x + 1\right) \bmod 1\right)}{e^{x}}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (exp (- x))))
   (if (<= (* (fmod (exp x) (sqrt (cos x))) t_0) 0.05)
     (* t_0 (fmod (fma x (* x 0.5) x) 1.0))
     (/ (fmod (+ x 1.0) 1.0) (exp x)))))
double code(double x) {
	double t_0 = exp(-x);
	double tmp;
	if ((fmod(exp(x), sqrt(cos(x))) * t_0) <= 0.05) {
		tmp = t_0 * fmod(fma(x, (x * 0.5), x), 1.0);
	} else {
		tmp = fmod((x + 1.0), 1.0) / exp(x);
	}
	return tmp;
}
function code(x)
	t_0 = exp(Float64(-x))
	tmp = 0.0
	if (Float64(rem(exp(x), sqrt(cos(x))) * t_0) <= 0.05)
		tmp = Float64(t_0 * rem(fma(x, Float64(x * 0.5), x), 1.0));
	else
		tmp = Float64(rem(Float64(x + 1.0), 1.0) / exp(x));
	end
	return tmp
end
code[x_] := Block[{t$95$0 = N[Exp[(-x)], $MachinePrecision]}, If[LessEqual[N[(N[With[{TMP1 = N[Exp[x], $MachinePrecision], TMP2 = N[Sqrt[N[Cos[x], $MachinePrecision]], $MachinePrecision]}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] * t$95$0), $MachinePrecision], 0.05], N[(t$95$0 * N[With[{TMP1 = N[(x * N[(x * 0.5), $MachinePrecision] + x), $MachinePrecision], TMP2 = 1.0}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision]), $MachinePrecision], N[(N[With[{TMP1 = N[(x + 1.0), $MachinePrecision], TMP2 = 1.0}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] / N[Exp[x], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := e^{-x}\\
\mathbf{if}\;\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot t\_0 \leq 0.05:\\
\;\;\;\;t\_0 \cdot \left(\left(\mathsf{fma}\left(x, x \cdot 0.5, x\right)\right) \bmod 1\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (*.f64 (fmod.f64 (exp.f64 x) (sqrt.f64 (cos.f64 x))) (exp.f64 (neg.f64 x))) < 0.050000000000000003

    1. Initial program 5.4%

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

      \[\leadsto \left(\left(e^{x}\right) \bmod \color{blue}{1}\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
    4. Step-by-step derivation
      1. Applied rewrites4.9%

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

        \[\leadsto \left(\color{blue}{\left(1 + x \cdot \left(1 + \frac{1}{2} \cdot x\right)\right)} \bmod 1\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
      3. Step-by-step derivation
        1. +-commutativeN/A

          \[\leadsto \left(\color{blue}{\left(x \cdot \left(1 + \frac{1}{2} \cdot x\right) + 1\right)} \bmod 1\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
        2. lower-fma.f64N/A

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

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

          \[\leadsto \left(\left(\mathsf{fma}\left(x, \color{blue}{x \cdot \frac{1}{2}} + 1, 1\right)\right) \bmod 1\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
        5. lower-fma.f644.9

          \[\leadsto \left(\left(\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, 0.5, 1\right)}, 1\right)\right) \bmod 1\right) \cdot e^{-x} \]
      4. Applied rewrites4.9%

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

        \[\leadsto \left(\left({x}^{2} \cdot \color{blue}{\left(\frac{1}{2} + \frac{1}{x}\right)}\right) \bmod 1\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
      6. Step-by-step derivation
        1. Applied rewrites50.4%

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

        if 0.050000000000000003 < (*.f64 (fmod.f64 (exp.f64 x) (sqrt.f64 (cos.f64 x))) (exp.f64 (neg.f64 x)))

        1. Initial program 8.6%

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

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

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

            \[\leadsto \left(\color{blue}{\left(1 + x\right)} \bmod 1\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
          3. Step-by-step derivation
            1. +-commutativeN/A

              \[\leadsto \left(\color{blue}{\left(x + 1\right)} \bmod 1\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
            2. lower-+.f6488.7

              \[\leadsto \left(\color{blue}{\left(x + 1\right)} \bmod 1\right) \cdot e^{-x} \]
          4. Applied rewrites88.7%

            \[\leadsto \left(\color{blue}{\left(x + 1\right)} \bmod 1\right) \cdot e^{-x} \]
          5. Step-by-step derivation
            1. lift-*.f64N/A

              \[\leadsto \color{blue}{\left(\left(x + 1\right) \bmod 1\right) \cdot e^{\mathsf{neg}\left(x\right)}} \]
            2. lift-exp.f64N/A

              \[\leadsto \left(\left(x + 1\right) \bmod 1\right) \cdot \color{blue}{e^{\mathsf{neg}\left(x\right)}} \]
            3. lift-neg.f64N/A

              \[\leadsto \left(\left(x + 1\right) \bmod 1\right) \cdot e^{\color{blue}{\mathsf{neg}\left(x\right)}} \]
            4. exp-negN/A

              \[\leadsto \left(\left(x + 1\right) \bmod 1\right) \cdot \color{blue}{\frac{1}{e^{x}}} \]
            5. un-div-invN/A

              \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) \bmod 1\right)}{e^{x}}} \]
            6. lower-/.f64N/A

              \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) \bmod 1\right)}{e^{x}}} \]
            7. lift-exp.f6488.7

              \[\leadsto \frac{\left(\left(x + 1\right) \bmod 1\right)}{\color{blue}{e^{x}}} \]
          6. Applied rewrites88.7%

            \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) \bmod 1\right)}{e^{x}}} \]
        5. Recombined 2 regimes into one program.
        6. Final simplification59.1%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \leq 0.05:\\ \;\;\;\;e^{-x} \cdot \left(\left(\mathsf{fma}\left(x, x \cdot 0.5, x\right)\right) \bmod 1\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(\left(x + 1\right) \bmod 1\right)}{e^{x}}\\ \end{array} \]
        7. Add Preprocessing

        Alternative 2: 25.6% accurate, 0.7× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \leq 2:\\ \;\;\;\;\frac{\left(\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, 0.5, 1\right), 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot -0.25, 1\right)\right)\right)}{x + 1}\\ \mathbf{else}:\\ \;\;\;\;\left(1 \bmod 1\right)\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= (* (fmod (exp x) (sqrt (cos x))) (exp (- x))) 2.0)
           (/ (fmod (fma x (fma x 0.5 1.0) 1.0) (fma x (* x -0.25) 1.0)) (+ x 1.0))
           (fmod 1.0 1.0)))
        double code(double x) {
        	double tmp;
        	if ((fmod(exp(x), sqrt(cos(x))) * exp(-x)) <= 2.0) {
        		tmp = fmod(fma(x, fma(x, 0.5, 1.0), 1.0), fma(x, (x * -0.25), 1.0)) / (x + 1.0);
        	} else {
        		tmp = fmod(1.0, 1.0);
        	}
        	return tmp;
        }
        
        function code(x)
        	tmp = 0.0
        	if (Float64(rem(exp(x), sqrt(cos(x))) * exp(Float64(-x))) <= 2.0)
        		tmp = Float64(rem(fma(x, fma(x, 0.5, 1.0), 1.0), fma(x, Float64(x * -0.25), 1.0)) / Float64(x + 1.0));
        	else
        		tmp = rem(1.0, 1.0);
        	end
        	return tmp
        end
        
        code[x_] := If[LessEqual[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], 2.0], N[(N[With[{TMP1 = N[(x * N[(x * 0.5 + 1.0), $MachinePrecision] + 1.0), $MachinePrecision], TMP2 = N[(x * N[(x * -0.25), $MachinePrecision] + 1.0), $MachinePrecision]}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision] / N[(x + 1.0), $MachinePrecision]), $MachinePrecision], N[With[{TMP1 = 1.0, TMP2 = 1.0}, Mod[Abs[TMP1], Abs[TMP2]] * Sign[TMP1]], $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right) \cdot e^{-x} \leq 2:\\
        \;\;\;\;\frac{\left(\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, 0.5, 1\right), 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot -0.25, 1\right)\right)\right)}{x + 1}\\
        
        \mathbf{else}:\\
        \;\;\;\;\left(1 \bmod 1\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (*.f64 (fmod.f64 (exp.f64 x) (sqrt.f64 (cos.f64 x))) (exp.f64 (neg.f64 x))) < 2

          1. Initial program 8.9%

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

            \[\leadsto \left(\left(e^{x}\right) \bmod \color{blue}{\left(1 + \frac{-1}{4} \cdot {x}^{2}\right)}\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
          4. Step-by-step derivation
            1. +-commutativeN/A

              \[\leadsto \left(\left(e^{x}\right) \bmod \color{blue}{\left(\frac{-1}{4} \cdot {x}^{2} + 1\right)}\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
            2. *-commutativeN/A

              \[\leadsto \left(\left(e^{x}\right) \bmod \left(\color{blue}{{x}^{2} \cdot \frac{-1}{4}} + 1\right)\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
            3. unpow2N/A

              \[\leadsto \left(\left(e^{x}\right) \bmod \left(\color{blue}{\left(x \cdot x\right)} \cdot \frac{-1}{4} + 1\right)\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
            4. associate-*l*N/A

              \[\leadsto \left(\left(e^{x}\right) \bmod \left(\color{blue}{x \cdot \left(x \cdot \frac{-1}{4}\right)} + 1\right)\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
            5. lower-fma.f64N/A

              \[\leadsto \left(\left(e^{x}\right) \bmod \color{blue}{\left(\mathsf{fma}\left(x, x \cdot \frac{-1}{4}, 1\right)\right)}\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
            6. lower-*.f648.6

              \[\leadsto \left(\left(e^{x}\right) \bmod \left(\mathsf{fma}\left(x, \color{blue}{x \cdot -0.25}, 1\right)\right)\right) \cdot e^{-x} \]
          5. Applied rewrites8.6%

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

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

              \[\leadsto \left(\color{blue}{\left(x \cdot \left(1 + \frac{1}{2} \cdot x\right) + 1\right)} \bmod \left(\mathsf{fma}\left(x, x \cdot \frac{-1}{4}, 1\right)\right)\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
            2. lower-fma.f64N/A

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

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

              \[\leadsto \left(\left(\mathsf{fma}\left(x, \color{blue}{x \cdot \frac{1}{2}} + 1, 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot \frac{-1}{4}, 1\right)\right)\right) \cdot e^{\mathsf{neg}\left(x\right)} \]
            5. lower-fma.f647.9

              \[\leadsto \left(\left(\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, 0.5, 1\right)}, 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot -0.25, 1\right)\right)\right) \cdot e^{-x} \]
          8. Applied rewrites7.9%

            \[\leadsto \left(\color{blue}{\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, 0.5, 1\right), 1\right)\right)} \bmod \left(\mathsf{fma}\left(x, x \cdot -0.25, 1\right)\right)\right) \cdot e^{-x} \]
          9. Step-by-step derivation
            1. lift-*.f64N/A

              \[\leadsto \color{blue}{\left(\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, \frac{1}{2}, 1\right), 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot \frac{-1}{4}, 1\right)\right)\right) \cdot e^{\mathsf{neg}\left(x\right)}} \]
            2. lift-exp.f64N/A

              \[\leadsto \left(\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, \frac{1}{2}, 1\right), 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot \frac{-1}{4}, 1\right)\right)\right) \cdot \color{blue}{e^{\mathsf{neg}\left(x\right)}} \]
            3. lift-neg.f64N/A

              \[\leadsto \left(\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, \frac{1}{2}, 1\right), 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot \frac{-1}{4}, 1\right)\right)\right) \cdot e^{\color{blue}{\mathsf{neg}\left(x\right)}} \]
            4. exp-negN/A

              \[\leadsto \left(\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, \frac{1}{2}, 1\right), 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot \frac{-1}{4}, 1\right)\right)\right) \cdot \color{blue}{\frac{1}{e^{x}}} \]
            5. un-div-invN/A

              \[\leadsto \color{blue}{\frac{\left(\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, \frac{1}{2}, 1\right), 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot \frac{-1}{4}, 1\right)\right)\right)}{e^{x}}} \]
            6. lower-/.f64N/A

              \[\leadsto \color{blue}{\frac{\left(\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, \frac{1}{2}, 1\right), 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot \frac{-1}{4}, 1\right)\right)\right)}{e^{x}}} \]
            7. lift-exp.f647.9

              \[\leadsto \frac{\left(\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, 0.5, 1\right), 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot -0.25, 1\right)\right)\right)}{\color{blue}{e^{x}}} \]
          10. Applied rewrites7.9%

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

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

              \[\leadsto \frac{\left(\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, \frac{1}{2}, 1\right), 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot \frac{-1}{4}, 1\right)\right)\right)}{\color{blue}{x + 1}} \]
            2. lower-+.f647.7

              \[\leadsto \frac{\left(\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, 0.5, 1\right), 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot -0.25, 1\right)\right)\right)}{\color{blue}{x + 1}} \]
          13. Applied rewrites7.7%

            \[\leadsto \frac{\left(\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, 0.5, 1\right), 1\right)\right) \bmod \left(\mathsf{fma}\left(x, x \cdot -0.25, 1\right)\right)\right)}{\color{blue}{x + 1}} \]

          if 2 < (*.f64 (fmod.f64 (exp.f64 x) (sqrt.f64 (cos.f64 x))) (exp.f64 (neg.f64 x)))

          1. Initial program 0.0%

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

            \[\leadsto \color{blue}{\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right)} \]
          4. Step-by-step derivation
            1. lower-fmod.f64N/A

              \[\leadsto \color{blue}{\left(\left(e^{x}\right) \bmod \left(\sqrt{\cos x}\right)\right)} \]
            2. lower-exp.f64N/A

              \[\leadsto \left(\color{blue}{\left(e^{x}\right)} \bmod \left(\sqrt{\cos x}\right)\right) \]
            3. lower-sqrt.f64N/A

              \[\leadsto \left(\left(e^{x}\right) \bmod \color{blue}{\left(\sqrt{\cos x}\right)}\right) \]
            4. lower-cos.f640.1

              \[\leadsto \left(\left(e^{x}\right) \bmod \left(\sqrt{\color{blue}{\cos x}}\right)\right) \]
          5. Applied rewrites0.1%

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

            \[\leadsto \left(\left(e^{x}\right) \bmod 1\right) \]
          7. Step-by-step derivation
            1. Applied rewrites0.1%

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

              \[\leadsto \left(1 \bmod 1\right) \]
            3. Step-by-step derivation
              1. Applied rewrites97.7%

                \[\leadsto \left(1 \bmod 1\right) \]
            4. Recombined 2 regimes into one program.
            5. Add Preprocessing

            Reproduce

            ?
            herbie shell --seed 2024225 
            (FPCore (x)
              :name "expfmod (used to be hard to sample)"
              :precision binary64
              (* (fmod (exp x) (sqrt (cos x))) (exp (- x))))