Development.Shake.Progress:decay from shake-0.15.5

Average Accuracy: 63.8% → 91.4%

Time: 22.3s

Precision: binary64

Cost: 12945.00

Math

\[\frac{x \cdot y + z \cdot \left(t - a\right)}{y + z \cdot \left(b - y\right)} \]

↓

\[\begin{array}{l} t_1 := y + z \cdot \left(b - y\right)\\ t_2 := z \cdot \left(t - a\right)\\ t_3 := \frac{x \cdot y + t_2}{t_1}\\ \mathbf{if}\;t_3 \leq -\infty:\\ \;\;\;\;\frac{x}{\frac{\mathsf{fma}\left(z, b - y, y\right)}{y}}\\ \mathbf{elif}\;t_3 \leq -2 \cdot 10^{-286}:\\ \;\;\;\;\frac{t_2}{t_1} + \frac{x \cdot y}{t_1}\\ \mathbf{elif}\;t_3 \leq 0 \lor \neg \left(t_3 \leq 4 \cdot 10^{+266}\right):\\ \;\;\;\;\frac{x \cdot \frac{y}{b - y}}{z} + \left(\frac{t - a}{b - y} - \frac{t - a}{\frac{{\left(b - y\right)}^{2}}{\frac{y}{z}}}\right)\\ \mathbf{else}:\\ \;\;\;\;t_3\\ \end{array} \]

FPCore

(FPCore (x y z t a b)
 :precision binary64
 (/ (+ (* x y) (* z (- t a))) (+ y (* z (- b y)))))

↓

(FPCore (x y z t a b)
 :precision binary64
 (let* ((t_1 (+ y (* z (- b y))))
        (t_2 (* z (- t a)))
        (t_3 (/ (+ (* x y) t_2) t_1)))
   (if (<= t_3 (- INFINITY))
     (/ x (/ (fma z (- b y) y) y))
     (if (<= t_3 -2e-286)
       (+ (/ t_2 t_1) (/ (* x y) t_1))
       (if (or (<= t_3 0.0) (not (<= t_3 4e+266)))
         (+
          (/ (* x (/ y (- b y))) z)
          (- (/ (- t a) (- b y)) (/ (- t a) (/ (pow (- b y) 2.0) (/ y z)))))
         t_3)))))

C

double code(double x, double y, double z, double t, double a, double b) {
	return ((x * y) + (z * (t - a))) / (y + (z * (b - y)));
}

↓

double code(double x, double y, double z, double t, double a, double b) {
	double t_1 = y + (z * (b - y));
	double t_2 = z * (t - a);
	double t_3 = ((x * y) + t_2) / t_1;
	double tmp;
	if (t_3 <= -((double) INFINITY)) {
		tmp = x / (fma(z, (b - y), y) / y);
	} else if (t_3 <= -2e-286) {
		tmp = (t_2 / t_1) + ((x * y) / t_1);
	} else if ((t_3 <= 0.0) || !(t_3 <= 4e+266)) {
		tmp = ((x * (y / (b - y))) / z) + (((t - a) / (b - y)) - ((t - a) / (pow((b - y), 2.0) / (y / z))));
	} else {
		tmp = t_3;
	}
	return tmp;
}

Julia

function code(x, y, z, t, a, b)
	return Float64(Float64(Float64(x * y) + Float64(z * Float64(t - a))) / Float64(y + Float64(z * Float64(b - y))))
end

↓

function code(x, y, z, t, a, b)
	t_1 = Float64(y + Float64(z * Float64(b - y)))
	t_2 = Float64(z * Float64(t - a))
	t_3 = Float64(Float64(Float64(x * y) + t_2) / t_1)
	tmp = 0.0
	if (t_3 <= Float64(-Inf))
		tmp = Float64(x / Float64(fma(z, Float64(b - y), y) / y));
	elseif (t_3 <= -2e-286)
		tmp = Float64(Float64(t_2 / t_1) + Float64(Float64(x * y) / t_1));
	elseif ((t_3 <= 0.0) || !(t_3 <= 4e+266))
		tmp = Float64(Float64(Float64(x * Float64(y / Float64(b - y))) / z) + Float64(Float64(Float64(t - a) / Float64(b - y)) - Float64(Float64(t - a) / Float64((Float64(b - y) ^ 2.0) / Float64(y / z)))));
	else
		tmp = t_3;
	end
	return tmp
end

Wolfram

code[x_, y_, z_, t_, a_, b_] := N[(N[(N[(x * y), $MachinePrecision] + N[(z * N[(t - a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(y + N[(z * N[(b - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]

↓

code[x_, y_, z_, t_, a_, b_] := Block[{t$95$1 = N[(y + N[(z * N[(b - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(z * N[(t - a), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[(N[(x * y), $MachinePrecision] + t$95$2), $MachinePrecision] / t$95$1), $MachinePrecision]}, If[LessEqual[t$95$3, (-Infinity)], N[(x / N[(N[(z * N[(b - y), $MachinePrecision] + y), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$3, -2e-286], N[(N[(t$95$2 / t$95$1), $MachinePrecision] + N[(N[(x * y), $MachinePrecision] / t$95$1), $MachinePrecision]), $MachinePrecision], If[Or[LessEqual[t$95$3, 0.0], N[Not[LessEqual[t$95$3, 4e+266]], $MachinePrecision]], N[(N[(N[(x * N[(y / N[(b - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / z), $MachinePrecision] + N[(N[(N[(t - a), $MachinePrecision] / N[(b - y), $MachinePrecision]), $MachinePrecision] - N[(N[(t - a), $MachinePrecision] / N[(N[Power[N[(b - y), $MachinePrecision], 2.0], $MachinePrecision] / N[(y / z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], t$95$3]]]]]]

Target

Original	63.8%
Target	72.1%
Herbie	91.4%

\[\frac{z \cdot t + y \cdot x}{y + z \cdot \left(b - y\right)} - \frac{a}{\left(b - y\right) + \frac{y}{z}} \]

Derivation

1. Split input into 4 regimes

2. if (/.f64 (+.f64 (*.f64 x y) (*.f64 z (-.f64 t a))) (+.f64 y (*.f64 z (-.f64 b y)))) < -inf.0

   1. Initial program 0.0%

      \[\frac{x \cdot y + z \cdot \left(t - a\right)}{y + z \cdot \left(b - y\right)} \]

   2. Taylor expanded in x around inf 1.0%

      \[\leadsto \color{blue}{\frac{y \cdot x}{y + \left(b - y\right) \cdot z}} \]

   3. Simplified 54.8%

      \[\leadsto \color{blue}{\frac{y}{\frac{\mathsf{fma}\left(z, b - y, y\right)}{x}}} \]
      Proof

      [Start] 1.0	\[ \frac{y \cdot x}{y + \left(b - y\right) \cdot z} \]
      associate-/l* [=>] 54.8	\[ \color{blue}{\frac{y}{\frac{y + \left(b - y\right) \cdot z}{x}}} \]
      *-commutative [=>] 54.8	\[ \frac{y}{\frac{y + \color{blue}{z \cdot \left(b - y\right)}}{x}} \]
      +-commutative [=>] 54.8	\[ \frac{y}{\frac{\color{blue}{z \cdot \left(b - y\right) + y}}{x}} \]
      fma-udef [<=] 54.8	\[ \frac{y}{\frac{\color{blue}{\mathsf{fma}\left(z, b - y, y\right)}}{x}} \]

   4. Taylor expanded in x around 0 1.0%

      \[\leadsto \color{blue}{\frac{y \cdot x}{z \cdot \left(b - y\right) + y}} \]

   5. Simplified 54.9%

      \[\leadsto \color{blue}{\frac{x}{\frac{\mathsf{fma}\left(z, b - y, y\right)}{y}}} \]
      Proof

      [Start] 1.0	\[ \frac{y \cdot x}{z \cdot \left(b - y\right) + y} \]
      *-commutative [=>] 1.0	\[ \frac{\color{blue}{x \cdot y}}{z \cdot \left(b - y\right) + y} \]
      fma-def [=>] 1.0	\[ \frac{x \cdot y}{\color{blue}{\mathsf{fma}\left(z, b - y, y\right)}} \]
      associate-/l* [=>] 54.9	\[ \color{blue}{\frac{x}{\frac{\mathsf{fma}\left(z, b - y, y\right)}{y}}} \]

   if -inf.0 < (/.f64 (+.f64 (*.f64 x y) (*.f64 z (-.f64 t a))) (+.f64 y (*.f64 z (-.f64 b y)))) < -2.0000000000000001e-286

   1. Initial program 99.5%

      \[\frac{x \cdot y + z \cdot \left(t - a\right)}{y + z \cdot \left(b - y\right)} \]

   2. Taylor expanded in x around inf 99.5%

      \[\leadsto \color{blue}{\frac{\left(t - a\right) \cdot z}{y + \left(b - y\right) \cdot z} + \frac{y \cdot x}{y + \left(b - y\right) \cdot z}} \]

   if -2.0000000000000001e-286 < (/.f64 (+.f64 (*.f64 x y) (*.f64 z (-.f64 t a))) (+.f64 y (*.f64 z (-.f64 b y)))) < 0.0 or 4.0000000000000001e266 < (/.f64 (+.f64 (*.f64 x y) (*.f64 z (-.f64 t a))) (+.f64 y (*.f64 z (-.f64 b y))))

   1. Initial program 11.9%

      \[\frac{x \cdot y + z \cdot \left(t - a\right)}{y + z \cdot \left(b - y\right)} \]

   2. Taylor expanded in z around inf 45.8%

      \[\leadsto \color{blue}{\left(\frac{y \cdot x}{z \cdot \left(b - y\right)} + \frac{t}{b - y}\right) - \left(\frac{\left(t - a\right) \cdot y}{z \cdot {\left(b - y\right)}^{2}} + \frac{a}{b - y}\right)} \]

   3. Simplified 85.2%

      \[\leadsto \color{blue}{\frac{\frac{y}{b - y} \cdot x}{z} + \left(\frac{t - a}{b - y} - \frac{t - a}{\frac{{\left(b - y\right)}^{2}}{\frac{y}{z}}}\right)} \]
      Proof

      [Start] 45.8	\[ \left(\frac{y \cdot x}{z \cdot \left(b - y\right)} + \frac{t}{b - y}\right) - \left(\frac{\left(t - a\right) \cdot y}{z \cdot {\left(b - y\right)}^{2}} + \frac{a}{b - y}\right) \]
      associate--l+ [=>] 45.8	\[ \color{blue}{\frac{y \cdot x}{z \cdot \left(b - y\right)} + \left(\frac{t}{b - y} - \left(\frac{\left(t - a\right) \cdot y}{z \cdot {\left(b - y\right)}^{2}} + \frac{a}{b - y}\right)\right)} \]
      *-commutative [<=] 45.8	\[ \frac{y \cdot x}{\color{blue}{\left(b - y\right) \cdot z}} + \left(\frac{t}{b - y} - \left(\frac{\left(t - a\right) \cdot y}{z \cdot {\left(b - y\right)}^{2}} + \frac{a}{b - y}\right)\right) \]
      times-frac [=>] 57.8	\[ \color{blue}{\frac{y}{b - y} \cdot \frac{x}{z}} + \left(\frac{t}{b - y} - \left(\frac{\left(t - a\right) \cdot y}{z \cdot {\left(b - y\right)}^{2}} + \frac{a}{b - y}\right)\right) \]
      associate-*r/ [=>] 57.9	\[ \color{blue}{\frac{\frac{y}{b - y} \cdot x}{z}} + \left(\frac{t}{b - y} - \left(\frac{\left(t - a\right) \cdot y}{z \cdot {\left(b - y\right)}^{2}} + \frac{a}{b - y}\right)\right) \]
      +-commutative [=>] 57.9	\[ \frac{\frac{y}{b - y} \cdot x}{z} + \left(\frac{t}{b - y} - \color{blue}{\left(\frac{a}{b - y} + \frac{\left(t - a\right) \cdot y}{z \cdot {\left(b - y\right)}^{2}}\right)}\right) \]
      *-commutative [<=] 57.9	\[ \frac{\frac{y}{b - y} \cdot x}{z} + \left(\frac{t}{b - y} - \left(\frac{a}{b - y} + \frac{\left(t - a\right) \cdot y}{\color{blue}{{\left(b - y\right)}^{2} \cdot z}}\right)\right) \]
      associate--r+ [=>] 57.9	\[ \frac{\frac{y}{b - y} \cdot x}{z} + \color{blue}{\left(\left(\frac{t}{b - y} - \frac{a}{b - y}\right) - \frac{\left(t - a\right) \cdot y}{{\left(b - y\right)}^{2} \cdot z}\right)} \]
      div-sub [<=] 57.9	\[ \frac{\frac{y}{b - y} \cdot x}{z} + \left(\color{blue}{\frac{t - a}{b - y}} - \frac{\left(t - a\right) \cdot y}{{\left(b - y\right)}^{2} \cdot z}\right) \]
      associate-/l* [=>] 85.3	\[ \frac{\frac{y}{b - y} \cdot x}{z} + \left(\frac{t - a}{b - y} - \color{blue}{\frac{t - a}{\frac{{\left(b - y\right)}^{2} \cdot z}{y}}}\right) \]
      associate-/l* [=>] 85.2	\[ \frac{\frac{y}{b - y} \cdot x}{z} + \left(\frac{t - a}{b - y} - \frac{t - a}{\color{blue}{\frac{{\left(b - y\right)}^{2}}{\frac{y}{z}}}}\right) \]

   if 0.0 < (/.f64 (+.f64 (*.f64 x y) (*.f64 z (-.f64 t a))) (+.f64 y (*.f64 z (-.f64 b y)))) < 4.0000000000000001e266

   1. Initial program 99.5%

      \[\frac{x \cdot y + z \cdot \left(t - a\right)}{y + z \cdot \left(b - y\right)} \]
3. Recombined 4 regimes into one program.

4. Final simplification 91.4%

   \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x \cdot y + z \cdot \left(t - a\right)}{y + z \cdot \left(b - y\right)} \leq -\infty:\\ \;\;\;\;\frac{x}{\frac{\mathsf{fma}\left(z, b - y, y\right)}{y}}\\ \mathbf{elif}\;\frac{x \cdot y + z \cdot \left(t - a\right)}{y + z \cdot \left(b - y\right)} \leq -2 \cdot 10^{-286}:\\ \;\;\;\;\frac{z \cdot \left(t - a\right)}{y + z \cdot \left(b - y\right)} + \frac{x \cdot y}{y + z \cdot \left(b - y\right)}\\ \mathbf{elif}\;\frac{x \cdot y + z \cdot \left(t - a\right)}{y + z \cdot \left(b - y\right)} \leq 0 \lor \neg \left(\frac{x \cdot y + z \cdot \left(t - a\right)}{y + z \cdot \left(b - y\right)} \leq 4 \cdot 10^{+266}\right):\\ \;\;\;\;\frac{x \cdot \frac{y}{b - y}}{z} + \left(\frac{t - a}{b - y} - \frac{t - a}{\frac{{\left(b - y\right)}^{2}}{\frac{y}{z}}}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{x \cdot y + z \cdot \left(t - a\right)}{y + z \cdot \left(b - y\right)}\\ \end{array} \]

Alternatives

Alternative 1
Accuracy	85.8%
Cost	8132.00

\[\begin{array}{l} t_1 := y + z \cdot \left(b - y\right)\\ t_2 := z \cdot \left(t - a\right)\\ t_3 := \frac{x \cdot y + t_2}{t_1}\\ \mathbf{if}\;t_3 \leq -\infty:\\ \;\;\;\;\frac{x}{\frac{\mathsf{fma}\left(z, b - y, y\right)}{y}}\\ \mathbf{elif}\;t_3 \leq -2 \cdot 10^{-286}:\\ \;\;\;\;\frac{t_2}{t_1} + \frac{x \cdot y}{t_1}\\ \mathbf{elif}\;t_3 \leq 0 \lor \neg \left(t_3 \leq 4 \cdot 10^{+266}\right):\\ \;\;\;\;\frac{t - a}{b - y}\\ \mathbf{else}:\\ \;\;\;\;t_3\\ \end{array} \]

Alternative 2
Accuracy	85.4%
Cost	5713.00

\[\begin{array}{l} t_1 := \frac{x \cdot y + z \cdot \left(t - a\right)}{y + z \cdot \left(b - y\right)}\\ \mathbf{if}\;t_1 \leq -\infty:\\ \;\;\;\;\frac{x}{1 - z}\\ \mathbf{elif}\;t_1 \leq -2 \cdot 10^{-286} \lor \neg \left(t_1 \leq 0\right) \land t_1 \leq 4 \cdot 10^{+266}:\\ \;\;\;\;t_1\\ \mathbf{else}:\\ \;\;\;\;\frac{t - a}{b - y}\\ \end{array} \]

Alternative 3
Accuracy	85.4%
Cost	5713.00

\[\begin{array}{l} t_1 := y + z \cdot \left(b - y\right)\\ t_2 := z \cdot \left(t - a\right)\\ t_3 := \frac{x \cdot y + t_2}{t_1}\\ \mathbf{if}\;t_3 \leq -\infty:\\ \;\;\;\;\frac{x}{1 - z}\\ \mathbf{elif}\;t_3 \leq -2 \cdot 10^{-286}:\\ \;\;\;\;\frac{t_2}{t_1} + \frac{x \cdot y}{t_1}\\ \mathbf{elif}\;t_3 \leq 0 \lor \neg \left(t_3 \leq 4 \cdot 10^{+266}\right):\\ \;\;\;\;\frac{t - a}{b - y}\\ \mathbf{else}:\\ \;\;\;\;t_3\\ \end{array} \]

Alternative 4
Accuracy	41.5%
Cost	1112.00

\[\begin{array}{l} t_1 := \frac{x}{1 - z}\\ t_2 := \frac{t}{b - y}\\ t_3 := \frac{a}{-b}\\ \mathbf{if}\;y \leq -1.8 \cdot 10^{+273}:\\ \;\;\;\;\frac{a - t}{y}\\ \mathbf{elif}\;y \leq -7.4 \cdot 10^{-18}:\\ \;\;\;\;t_1\\ \mathbf{elif}\;y \leq -6.8 \cdot 10^{-242}:\\ \;\;\;\;t_2\\ \mathbf{elif}\;y \leq 2.26 \cdot 10^{-259}:\\ \;\;\;\;t_3\\ \mathbf{elif}\;y \leq 1.38 \cdot 10^{-108}:\\ \;\;\;\;t_2\\ \mathbf{elif}\;y \leq 1.7 \cdot 10^{-61}:\\ \;\;\;\;t_3\\ \mathbf{else}:\\ \;\;\;\;t_1\\ \end{array} \]

Alternative 5
Accuracy	48.3%
Cost	1112.00

\[\begin{array}{l} t_1 := \frac{x}{1 - z}\\ t_2 := \frac{t - a}{b}\\ \mathbf{if}\;y \leq -1.8 \cdot 10^{+273}:\\ \;\;\;\;\frac{a - t}{y}\\ \mathbf{elif}\;y \leq -2.85 \cdot 10^{-22}:\\ \;\;\;\;t_1\\ \mathbf{elif}\;y \leq -3.6 \cdot 10^{-83}:\\ \;\;\;\;t_2\\ \mathbf{elif}\;y \leq -4.1 \cdot 10^{-112}:\\ \;\;\;\;\frac{y}{z} \cdot \frac{x}{b}\\ \mathbf{elif}\;y \leq -5.2 \cdot 10^{-198}:\\ \;\;\;\;\frac{t}{b - y}\\ \mathbf{elif}\;y \leq 1.15 \cdot 10^{-76}:\\ \;\;\;\;t_2\\ \mathbf{else}:\\ \;\;\;\;t_1\\ \end{array} \]

Alternative 6
Accuracy	42.7%
Cost	980.00

\[\begin{array}{l} t_1 := \frac{t}{b - y}\\ t_2 := \frac{a}{-b}\\ t_3 := \frac{x}{1 - z}\\ \mathbf{if}\;y \leq -3 \cdot 10^{-17}:\\ \;\;\;\;t_3\\ \mathbf{elif}\;y \leq -2.25 \cdot 10^{-241}:\\ \;\;\;\;t_1\\ \mathbf{elif}\;y \leq 7.5 \cdot 10^{-259}:\\ \;\;\;\;t_2\\ \mathbf{elif}\;y \leq 2.3 \cdot 10^{-109}:\\ \;\;\;\;t_1\\ \mathbf{elif}\;y \leq 3.6 \cdot 10^{-62}:\\ \;\;\;\;t_2\\ \mathbf{else}:\\ \;\;\;\;t_3\\ \end{array} \]

Alternative 7
Accuracy	35.5%
Cost	917.00

\[\begin{array}{l} t_1 := \frac{a}{-b}\\ \mathbf{if}\;z \leq -2.1 \cdot 10^{+206}:\\ \;\;\;\;t_1\\ \mathbf{elif}\;z \leq -4.8 \cdot 10^{-44}:\\ \;\;\;\;\frac{t}{b}\\ \mathbf{elif}\;z \leq 1.7 \cdot 10^{-62}:\\ \;\;\;\;x\\ \mathbf{elif}\;z \leq 2.7 \cdot 10^{+101} \lor \neg \left(z \leq 6.8 \cdot 10^{+248}\right):\\ \;\;\;\;t_1\\ \mathbf{else}:\\ \;\;\;\;\frac{a}{y}\\ \end{array} \]

Alternative 8
Accuracy	35.4%
Cost	917.00

\[\begin{array}{l} t_1 := \frac{a}{-b}\\ \mathbf{if}\;z \leq -1.4 \cdot 10^{+206}:\\ \;\;\;\;t_1\\ \mathbf{elif}\;z \leq -5.2 \cdot 10^{-44}:\\ \;\;\;\;\frac{t}{b}\\ \mathbf{elif}\;z \leq 1.75 \cdot 10^{-62}:\\ \;\;\;\;x\\ \mathbf{elif}\;z \leq 7.5 \cdot 10^{+82} \lor \neg \left(z \leq 2.45 \cdot 10^{+291}\right):\\ \;\;\;\;t_1\\ \mathbf{else}:\\ \;\;\;\;\frac{-t}{y}\\ \end{array} \]

Alternative 9
Accuracy	72.9%
Cost	841.00

\[\begin{array}{l} \mathbf{if}\;z \leq -5.2 \cdot 10^{-44} \lor \neg \left(z \leq 1.8 \cdot 10^{-62}\right):\\ \;\;\;\;\frac{t - a}{b - y}\\ \mathbf{else}:\\ \;\;\;\;x + \frac{z \cdot \left(t - a\right)}{y}\\ \end{array} \]

Alternative 10
Accuracy	50.6%
Cost	717.00

\[\begin{array}{l} \mathbf{if}\;y \leq -1.8 \cdot 10^{+273}:\\ \;\;\;\;\frac{a - t}{y}\\ \mathbf{elif}\;y \leq -5.4 \cdot 10^{-22} \lor \neg \left(y \leq 1.15 \cdot 10^{-76}\right):\\ \;\;\;\;\frac{x}{1 - z}\\ \mathbf{else}:\\ \;\;\;\;\frac{t - a}{b}\\ \end{array} \]

Alternative 11
Accuracy	63.2%
Cost	713.00

\[\begin{array}{l} \mathbf{if}\;z \leq -3.4 \cdot 10^{-46} \lor \neg \left(z \leq 9 \cdot 10^{-114}\right):\\ \;\;\;\;\frac{t - a}{b - y}\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \]

Alternative 12
Accuracy	45.3%
Cost	585.00

\[\begin{array}{l} \mathbf{if}\;z \leq -1.65 \cdot 10^{-45} \lor \neg \left(z \leq 2.6 \cdot 10^{-39}\right):\\ \;\;\;\;\frac{t}{b - y}\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \]

Alternative 13
Accuracy	34.6%
Cost	456.00

\[\begin{array}{l} \mathbf{if}\;z \leq -1.45 \cdot 10^{+21}:\\ \;\;\;\;\frac{a}{y}\\ \mathbf{elif}\;z \leq 600:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;\frac{a}{y}\\ \end{array} \]

Alternative 14
Accuracy	36.7%
Cost	456.00

\[\begin{array}{l} \mathbf{if}\;z \leq -5.2 \cdot 10^{-44}:\\ \;\;\;\;\frac{t}{b}\\ \mathbf{elif}\;z \leq 2.9 \cdot 10^{-39}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;\frac{t}{b}\\ \end{array} \]

Alternative 15
Accuracy	26.6%
Cost	64.00

\[x \]

Reproduce

herbie shell --seed 2023096 
(FPCore (x y z t a b)
  :name "Development.Shake.Progress:decay from shake-0.15.5"
  :precision binary64

  :herbie-target
  (- (/ (+ (* z t) (* y x)) (+ y (* z (- b y)))) (/ a (+ (- b y) (/ y z))))

  (/ (+ (* x y) (* z (- t a))) (+ y (* z (- b y)))))