Average Error: 22.4 → 0.2
Time: 16.5s
Precision: binary64
Cost: 968
\[1 - \frac{\left(1 - x\right) \cdot y}{y + 1} \]
\[\begin{array}{l} \mathbf{if}\;y \leq -3962435670.6258354:\\ \;\;\;\;x + \frac{-1}{y} \cdot \left(-1 + \frac{1}{y}\right)\\ \mathbf{elif}\;y \leq 244.49319934554606:\\ \;\;\;\;1 - \frac{y \cdot \left(1 - x\right)}{y + 1}\\ \mathbf{else}:\\ \;\;\;\;x + \frac{\frac{-1}{y} + 1}{y}\\ \end{array} \]
(FPCore (x y) :precision binary64 (- 1.0 (/ (* (- 1.0 x) y) (+ y 1.0))))
(FPCore (x y)
 :precision binary64
 (if (<= y -3962435670.6258354)
   (+ x (* (/ -1.0 y) (+ -1.0 (/ 1.0 y))))
   (if (<= y 244.49319934554606)
     (- 1.0 (/ (* y (- 1.0 x)) (+ y 1.0)))
     (+ x (/ (+ (/ -1.0 y) 1.0) y)))))
double code(double x, double y) {
	return 1.0 - (((1.0 - x) * y) / (y + 1.0));
}
double code(double x, double y) {
	double tmp;
	if (y <= -3962435670.6258354) {
		tmp = x + ((-1.0 / y) * (-1.0 + (1.0 / y)));
	} else if (y <= 244.49319934554606) {
		tmp = 1.0 - ((y * (1.0 - x)) / (y + 1.0));
	} else {
		tmp = x + (((-1.0 / y) + 1.0) / y);
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = 1.0d0 - (((1.0d0 - x) * y) / (y + 1.0d0))
end function
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (y <= (-3962435670.6258354d0)) then
        tmp = x + (((-1.0d0) / y) * ((-1.0d0) + (1.0d0 / y)))
    else if (y <= 244.49319934554606d0) then
        tmp = 1.0d0 - ((y * (1.0d0 - x)) / (y + 1.0d0))
    else
        tmp = x + ((((-1.0d0) / y) + 1.0d0) / y)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	return 1.0 - (((1.0 - x) * y) / (y + 1.0));
}
public static double code(double x, double y) {
	double tmp;
	if (y <= -3962435670.6258354) {
		tmp = x + ((-1.0 / y) * (-1.0 + (1.0 / y)));
	} else if (y <= 244.49319934554606) {
		tmp = 1.0 - ((y * (1.0 - x)) / (y + 1.0));
	} else {
		tmp = x + (((-1.0 / y) + 1.0) / y);
	}
	return tmp;
}
def code(x, y):
	return 1.0 - (((1.0 - x) * y) / (y + 1.0))
def code(x, y):
	tmp = 0
	if y <= -3962435670.6258354:
		tmp = x + ((-1.0 / y) * (-1.0 + (1.0 / y)))
	elif y <= 244.49319934554606:
		tmp = 1.0 - ((y * (1.0 - x)) / (y + 1.0))
	else:
		tmp = x + (((-1.0 / y) + 1.0) / y)
	return tmp
function code(x, y)
	return Float64(1.0 - Float64(Float64(Float64(1.0 - x) * y) / Float64(y + 1.0)))
end
function code(x, y)
	tmp = 0.0
	if (y <= -3962435670.6258354)
		tmp = Float64(x + Float64(Float64(-1.0 / y) * Float64(-1.0 + Float64(1.0 / y))));
	elseif (y <= 244.49319934554606)
		tmp = Float64(1.0 - Float64(Float64(y * Float64(1.0 - x)) / Float64(y + 1.0)));
	else
		tmp = Float64(x + Float64(Float64(Float64(-1.0 / y) + 1.0) / y));
	end
	return tmp
end
function tmp = code(x, y)
	tmp = 1.0 - (((1.0 - x) * y) / (y + 1.0));
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -3962435670.6258354)
		tmp = x + ((-1.0 / y) * (-1.0 + (1.0 / y)));
	elseif (y <= 244.49319934554606)
		tmp = 1.0 - ((y * (1.0 - x)) / (y + 1.0));
	else
		tmp = x + (((-1.0 / y) + 1.0) / y);
	end
	tmp_2 = tmp;
end
code[x_, y_] := N[(1.0 - N[(N[(N[(1.0 - x), $MachinePrecision] * y), $MachinePrecision] / N[(y + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
code[x_, y_] := If[LessEqual[y, -3962435670.6258354], N[(x + N[(N[(-1.0 / y), $MachinePrecision] * N[(-1.0 + N[(1.0 / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 244.49319934554606], N[(1.0 - N[(N[(y * N[(1.0 - x), $MachinePrecision]), $MachinePrecision] / N[(y + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x + N[(N[(N[(-1.0 / y), $MachinePrecision] + 1.0), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision]]]
1 - \frac{\left(1 - x\right) \cdot y}{y + 1}
\begin{array}{l}
\mathbf{if}\;y \leq -3962435670.6258354:\\
\;\;\;\;x + \frac{-1}{y} \cdot \left(-1 + \frac{1}{y}\right)\\

\mathbf{elif}\;y \leq 244.49319934554606:\\
\;\;\;\;1 - \frac{y \cdot \left(1 - x\right)}{y + 1}\\

\mathbf{else}:\\
\;\;\;\;x + \frac{\frac{-1}{y} + 1}{y}\\


\end{array}

Error

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original22.4
Target0.2
Herbie0.2
\[\begin{array}{l} \mathbf{if}\;y < -3693.8482788297247:\\ \;\;\;\;\frac{1}{y} - \left(\frac{x}{y} - x\right)\\ \mathbf{elif}\;y < 6799310503.41891:\\ \;\;\;\;1 - \frac{\left(1 - x\right) \cdot y}{y + 1}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{y} - \left(\frac{x}{y} - x\right)\\ \end{array} \]

Derivation

  1. Split input into 3 regimes
  2. if y < -3962435670.6258354

    1. Initial program 46.1

      \[1 - \frac{\left(1 - x\right) \cdot y}{y + 1} \]
    2. Taylor expanded in y around inf 0.0

      \[\leadsto \color{blue}{\left(\frac{1}{y} + \left(-1 \cdot \frac{1 + -1 \cdot x}{{y}^{2}} + x\right)\right) - \frac{x}{y}} \]
    3. Simplified0.0

      \[\leadsto \color{blue}{x + \frac{-1 + x}{y} \cdot \left(\frac{1}{y} + -1\right)} \]
      Proof
      (+.f64 x (*.f64 (/.f64 (+.f64 -1 x) y) (+.f64 (/.f64 1 y) -1))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (*.f64 (/.f64 (Rewrite<= +-commutative_binary64 (+.f64 x -1)) y) (+.f64 (/.f64 1 y) -1))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (*.f64 (/.f64 (+.f64 x (Rewrite<= metadata-eval (neg.f64 1))) y) (+.f64 (/.f64 1 y) -1))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (*.f64 (/.f64 (Rewrite<= sub-neg_binary64 (-.f64 x 1)) y) (+.f64 (/.f64 1 y) -1))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (Rewrite<= distribute-rgt-out_binary64 (+.f64 (*.f64 (/.f64 1 y) (/.f64 (-.f64 x 1) y)) (*.f64 -1 (/.f64 (-.f64 x 1) y))))): 1 points increase in error, 1 points decrease in error
      (+.f64 x (+.f64 (Rewrite<= times-frac_binary64 (/.f64 (*.f64 1 (-.f64 x 1)) (*.f64 y y))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 12 points increase in error, 12 points decrease in error
      (+.f64 x (+.f64 (/.f64 (*.f64 1 (-.f64 x 1)) (Rewrite<= unpow2_binary64 (pow.f64 y 2))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (+.f64 (/.f64 (*.f64 1 (-.f64 x 1)) (Rewrite<= *-lft-identity_binary64 (*.f64 1 (pow.f64 y 2)))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (+.f64 (Rewrite=> times-frac_binary64 (*.f64 (/.f64 1 1) (/.f64 (-.f64 x 1) (pow.f64 y 2)))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (+.f64 (*.f64 (Rewrite=> metadata-eval 1) (/.f64 (-.f64 x 1) (pow.f64 y 2))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (+.f64 (Rewrite=> *-lft-identity_binary64 (/.f64 (-.f64 x 1) (pow.f64 y 2))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= associate-+l+_binary64 (+.f64 (+.f64 x (/.f64 (-.f64 x 1) (pow.f64 y 2))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 1 points increase in error, 0 points decrease in error
      (+.f64 (Rewrite=> +-commutative_binary64 (+.f64 (/.f64 (-.f64 x 1) (pow.f64 y 2)) x)) (*.f64 -1 (/.f64 (-.f64 x 1) y))): 0 points increase in error, 0 points decrease in error
      (Rewrite=> associate-+l+_binary64 (+.f64 (/.f64 (-.f64 x 1) (pow.f64 y 2)) (+.f64 x (*.f64 -1 (/.f64 (-.f64 x 1) y))))): 0 points increase in error, 0 points decrease in error
      (+.f64 (/.f64 (-.f64 x 1) (pow.f64 y 2)) (Rewrite<= +-commutative_binary64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= +-commutative_binary64 (+.f64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x) (/.f64 (-.f64 x 1) (pow.f64 y 2)))): 0 points increase in error, 0 points decrease in error
      (+.f64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x) (Rewrite=> div-sub_binary64 (-.f64 (/.f64 x (pow.f64 y 2)) (/.f64 1 (pow.f64 y 2))))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= associate--l+_binary64 (-.f64 (+.f64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x) (/.f64 x (pow.f64 y 2))) (/.f64 1 (pow.f64 y 2)))): 0 points increase in error, 0 points decrease in error
      (-.f64 (Rewrite<= +-commutative_binary64 (+.f64 (/.f64 x (pow.f64 y 2)) (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x))) (/.f64 1 (pow.f64 y 2))): 0 points increase in error, 0 points decrease in error
      (Rewrite=> associate--l+_binary64 (+.f64 (/.f64 x (pow.f64 y 2)) (-.f64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x) (/.f64 1 (pow.f64 y 2))))): 0 points increase in error, 0 points decrease in error
      (Rewrite=> +-commutative_binary64 (+.f64 (-.f64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x) (/.f64 1 (pow.f64 y 2))) (/.f64 x (pow.f64 y 2)))): 0 points increase in error, 0 points decrease in error
      (+.f64 (Rewrite=> associate--l+_binary64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (-.f64 x (/.f64 1 (pow.f64 y 2))))) (/.f64 x (pow.f64 y 2))): 0 points increase in error, 0 points decrease in error
      (Rewrite=> associate-+l+_binary64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (+.f64 (-.f64 x (/.f64 1 (pow.f64 y 2))) (/.f64 x (pow.f64 y 2))))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (Rewrite<= associate--r-_binary64 (-.f64 x (-.f64 (/.f64 1 (pow.f64 y 2)) (/.f64 x (pow.f64 y 2)))))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (-.f64 x (Rewrite<= div-sub_binary64 (/.f64 (-.f64 1 x) (pow.f64 y 2))))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (-.f64 x (/.f64 (Rewrite=> sub-neg_binary64 (+.f64 1 (neg.f64 x))) (pow.f64 y 2)))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (-.f64 x (/.f64 (+.f64 1 (Rewrite<= mul-1-neg_binary64 (*.f64 -1 x))) (pow.f64 y 2)))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (Rewrite<= unsub-neg_binary64 (+.f64 x (neg.f64 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2)))))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (+.f64 x (Rewrite<= mul-1-neg_binary64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2)))))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (Rewrite<= +-commutative_binary64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= +-commutative_binary64 (+.f64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (+.f64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x) (Rewrite=> mul-1-neg_binary64 (neg.f64 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (Rewrite=> unsub-neg_binary64 (-.f64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x) (/.f64 (-.f64 x 1) y))): 0 points increase in error, 0 points decrease in error
      (-.f64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x) (Rewrite=> div-sub_binary64 (-.f64 (/.f64 x y) (/.f64 1 y)))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= associate-+l-_binary64 (+.f64 (-.f64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x) (/.f64 x y)) (/.f64 1 y))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= +-commutative_binary64 (+.f64 (/.f64 1 y) (-.f64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x) (/.f64 x y)))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= associate--l+_binary64 (-.f64 (+.f64 (/.f64 1 y) (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x)) (/.f64 x y))): 0 points increase in error, 0 points decrease in error
    4. Taylor expanded in x around 0 0.2

      \[\leadsto x + \color{blue}{\frac{-1}{y}} \cdot \left(\frac{1}{y} + -1\right) \]

    if -3962435670.6258354 < y < 244.49319934554606

    1. Initial program 0.1

      \[1 - \frac{\left(1 - x\right) \cdot y}{y + 1} \]

    if 244.49319934554606 < y

    1. Initial program 44.6

      \[1 - \frac{\left(1 - x\right) \cdot y}{y + 1} \]
    2. Taylor expanded in y around inf 0.2

      \[\leadsto \color{blue}{\left(\frac{1}{y} + \left(-1 \cdot \frac{1 + -1 \cdot x}{{y}^{2}} + x\right)\right) - \frac{x}{y}} \]
    3. Simplified0.2

      \[\leadsto \color{blue}{x + \frac{-1 + x}{y} \cdot \left(\frac{1}{y} + -1\right)} \]
      Proof
      (+.f64 x (*.f64 (/.f64 (+.f64 -1 x) y) (+.f64 (/.f64 1 y) -1))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (*.f64 (/.f64 (Rewrite<= +-commutative_binary64 (+.f64 x -1)) y) (+.f64 (/.f64 1 y) -1))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (*.f64 (/.f64 (+.f64 x (Rewrite<= metadata-eval (neg.f64 1))) y) (+.f64 (/.f64 1 y) -1))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (*.f64 (/.f64 (Rewrite<= sub-neg_binary64 (-.f64 x 1)) y) (+.f64 (/.f64 1 y) -1))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (Rewrite<= distribute-rgt-out_binary64 (+.f64 (*.f64 (/.f64 1 y) (/.f64 (-.f64 x 1) y)) (*.f64 -1 (/.f64 (-.f64 x 1) y))))): 1 points increase in error, 1 points decrease in error
      (+.f64 x (+.f64 (Rewrite<= times-frac_binary64 (/.f64 (*.f64 1 (-.f64 x 1)) (*.f64 y y))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 12 points increase in error, 12 points decrease in error
      (+.f64 x (+.f64 (/.f64 (*.f64 1 (-.f64 x 1)) (Rewrite<= unpow2_binary64 (pow.f64 y 2))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (+.f64 (/.f64 (*.f64 1 (-.f64 x 1)) (Rewrite<= *-lft-identity_binary64 (*.f64 1 (pow.f64 y 2)))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (+.f64 (Rewrite=> times-frac_binary64 (*.f64 (/.f64 1 1) (/.f64 (-.f64 x 1) (pow.f64 y 2)))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (+.f64 (*.f64 (Rewrite=> metadata-eval 1) (/.f64 (-.f64 x 1) (pow.f64 y 2))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (+.f64 x (+.f64 (Rewrite=> *-lft-identity_binary64 (/.f64 (-.f64 x 1) (pow.f64 y 2))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= associate-+l+_binary64 (+.f64 (+.f64 x (/.f64 (-.f64 x 1) (pow.f64 y 2))) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 1 points increase in error, 0 points decrease in error
      (+.f64 (Rewrite=> +-commutative_binary64 (+.f64 (/.f64 (-.f64 x 1) (pow.f64 y 2)) x)) (*.f64 -1 (/.f64 (-.f64 x 1) y))): 0 points increase in error, 0 points decrease in error
      (Rewrite=> associate-+l+_binary64 (+.f64 (/.f64 (-.f64 x 1) (pow.f64 y 2)) (+.f64 x (*.f64 -1 (/.f64 (-.f64 x 1) y))))): 0 points increase in error, 0 points decrease in error
      (+.f64 (/.f64 (-.f64 x 1) (pow.f64 y 2)) (Rewrite<= +-commutative_binary64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= +-commutative_binary64 (+.f64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x) (/.f64 (-.f64 x 1) (pow.f64 y 2)))): 0 points increase in error, 0 points decrease in error
      (+.f64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x) (Rewrite=> div-sub_binary64 (-.f64 (/.f64 x (pow.f64 y 2)) (/.f64 1 (pow.f64 y 2))))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= associate--l+_binary64 (-.f64 (+.f64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x) (/.f64 x (pow.f64 y 2))) (/.f64 1 (pow.f64 y 2)))): 0 points increase in error, 0 points decrease in error
      (-.f64 (Rewrite<= +-commutative_binary64 (+.f64 (/.f64 x (pow.f64 y 2)) (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x))) (/.f64 1 (pow.f64 y 2))): 0 points increase in error, 0 points decrease in error
      (Rewrite=> associate--l+_binary64 (+.f64 (/.f64 x (pow.f64 y 2)) (-.f64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x) (/.f64 1 (pow.f64 y 2))))): 0 points increase in error, 0 points decrease in error
      (Rewrite=> +-commutative_binary64 (+.f64 (-.f64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) x) (/.f64 1 (pow.f64 y 2))) (/.f64 x (pow.f64 y 2)))): 0 points increase in error, 0 points decrease in error
      (+.f64 (Rewrite=> associate--l+_binary64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (-.f64 x (/.f64 1 (pow.f64 y 2))))) (/.f64 x (pow.f64 y 2))): 0 points increase in error, 0 points decrease in error
      (Rewrite=> associate-+l+_binary64 (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (+.f64 (-.f64 x (/.f64 1 (pow.f64 y 2))) (/.f64 x (pow.f64 y 2))))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (Rewrite<= associate--r-_binary64 (-.f64 x (-.f64 (/.f64 1 (pow.f64 y 2)) (/.f64 x (pow.f64 y 2)))))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (-.f64 x (Rewrite<= div-sub_binary64 (/.f64 (-.f64 1 x) (pow.f64 y 2))))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (-.f64 x (/.f64 (Rewrite=> sub-neg_binary64 (+.f64 1 (neg.f64 x))) (pow.f64 y 2)))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (-.f64 x (/.f64 (+.f64 1 (Rewrite<= mul-1-neg_binary64 (*.f64 -1 x))) (pow.f64 y 2)))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (Rewrite<= unsub-neg_binary64 (+.f64 x (neg.f64 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2)))))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (+.f64 x (Rewrite<= mul-1-neg_binary64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2)))))): 0 points increase in error, 0 points decrease in error
      (+.f64 (*.f64 -1 (/.f64 (-.f64 x 1) y)) (Rewrite<= +-commutative_binary64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= +-commutative_binary64 (+.f64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x) (*.f64 -1 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (+.f64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x) (Rewrite=> mul-1-neg_binary64 (neg.f64 (/.f64 (-.f64 x 1) y)))): 0 points increase in error, 0 points decrease in error
      (Rewrite=> unsub-neg_binary64 (-.f64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x) (/.f64 (-.f64 x 1) y))): 0 points increase in error, 0 points decrease in error
      (-.f64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x) (Rewrite=> div-sub_binary64 (-.f64 (/.f64 x y) (/.f64 1 y)))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= associate-+l-_binary64 (+.f64 (-.f64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x) (/.f64 x y)) (/.f64 1 y))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= +-commutative_binary64 (+.f64 (/.f64 1 y) (-.f64 (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x) (/.f64 x y)))): 0 points increase in error, 0 points decrease in error
      (Rewrite<= associate--l+_binary64 (-.f64 (+.f64 (/.f64 1 y) (+.f64 (*.f64 -1 (/.f64 (+.f64 1 (*.f64 -1 x)) (pow.f64 y 2))) x)) (/.f64 x y))): 0 points increase in error, 0 points decrease in error
    4. Taylor expanded in x around 0 0.5

      \[\leadsto x + \color{blue}{\frac{-1}{y}} \cdot \left(\frac{1}{y} + -1\right) \]
    5. Taylor expanded in x around 0 0.5

      \[\leadsto \color{blue}{-1 \cdot \frac{\frac{1}{y} - 1}{y} + x} \]
    6. Simplified0.5

      \[\leadsto \color{blue}{\frac{1 - \frac{1}{y}}{y} + x} \]
      Proof
      (+.f64 (/.f64 (-.f64 1 (/.f64 1 y)) y) x): 0 points increase in error, 0 points decrease in error
      (+.f64 (/.f64 (Rewrite<= unsub-neg_binary64 (+.f64 1 (neg.f64 (/.f64 1 y)))) y) x): 0 points increase in error, 0 points decrease in error
      (+.f64 (/.f64 (Rewrite<= +-commutative_binary64 (+.f64 (neg.f64 (/.f64 1 y)) 1)) y) x): 0 points increase in error, 0 points decrease in error
      (+.f64 (/.f64 (+.f64 (Rewrite=> neg-sub0_binary64 (-.f64 0 (/.f64 1 y))) 1) y) x): 0 points increase in error, 0 points decrease in error
      (+.f64 (/.f64 (Rewrite<= associate--r-_binary64 (-.f64 0 (-.f64 (/.f64 1 y) 1))) y) x): 0 points increase in error, 0 points decrease in error
      (+.f64 (/.f64 (Rewrite<= neg-sub0_binary64 (neg.f64 (-.f64 (/.f64 1 y) 1))) y) x): 0 points increase in error, 0 points decrease in error
      (+.f64 (Rewrite<= distribute-neg-frac_binary64 (neg.f64 (/.f64 (-.f64 (/.f64 1 y) 1) y))) x): 0 points increase in error, 0 points decrease in error
      (+.f64 (Rewrite<= mul-1-neg_binary64 (*.f64 -1 (/.f64 (-.f64 (/.f64 1 y) 1) y))) x): 0 points increase in error, 0 points decrease in error
  3. Recombined 3 regimes into one program.
  4. Final simplification0.2

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -3962435670.6258354:\\ \;\;\;\;x + \frac{-1}{y} \cdot \left(-1 + \frac{1}{y}\right)\\ \mathbf{elif}\;y \leq 244.49319934554606:\\ \;\;\;\;1 - \frac{y \cdot \left(1 - x\right)}{y + 1}\\ \mathbf{else}:\\ \;\;\;\;x + \frac{\frac{-1}{y} + 1}{y}\\ \end{array} \]

Alternatives

Alternative 1
Error1.1
Cost968
\[\begin{array}{l} t_0 := x + \frac{-1}{y} \cdot \left(-1 + \frac{1}{y}\right)\\ \mathbf{if}\;y \leq -564.3173039255272:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq 2.974344203570807 \cdot 10^{-8}:\\ \;\;\;\;1 - \left(y - y \cdot x\right)\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \]
Alternative 2
Error9.5
Cost848
\[\begin{array}{l} t_0 := x + \frac{1}{y}\\ \mathbf{if}\;y \leq -564.3173039255272:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq 1.2084538562841602 \cdot 10^{-164}:\\ \;\;\;\;1 - y\\ \mathbf{elif}\;y \leq 1.6986565015851093 \cdot 10^{-122}:\\ \;\;\;\;y \cdot x\\ \mathbf{elif}\;y \leq 2.974344203570807 \cdot 10^{-8}:\\ \;\;\;\;1 - y\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \]
Alternative 3
Error1.1
Cost840
\[\begin{array}{l} t_0 := x + \frac{\frac{-1}{y} + 1}{y}\\ \mathbf{if}\;y \leq -564.3173039255272:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq 2.974344203570807 \cdot 10^{-8}:\\ \;\;\;\;1 - \left(y - y \cdot x\right)\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \]
Alternative 4
Error17.0
Cost720
\[\begin{array}{l} \mathbf{if}\;y \leq -564.3173039255272:\\ \;\;\;\;x\\ \mathbf{elif}\;y \leq 1.2084538562841602 \cdot 10^{-164}:\\ \;\;\;\;1 - y\\ \mathbf{elif}\;y \leq 1.6986565015851093 \cdot 10^{-122}:\\ \;\;\;\;y \cdot x\\ \mathbf{elif}\;y \leq 2.974344203570807 \cdot 10^{-8}:\\ \;\;\;\;1 - y\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \]
Alternative 5
Error1.3
Cost712
\[\begin{array}{l} t_0 := x + \frac{1}{y}\\ \mathbf{if}\;y \leq -564.3173039255272:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq 2.974344203570807 \cdot 10^{-8}:\\ \;\;\;\;1 - \left(y - y \cdot x\right)\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \]
Alternative 6
Error1.1
Cost712
\[\begin{array}{l} t_0 := x + \frac{1 - x}{y}\\ \mathbf{if}\;y \leq -564.3173039255272:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq 2.974344203570807 \cdot 10^{-8}:\\ \;\;\;\;1 - \left(y - y \cdot x\right)\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \]
Alternative 7
Error1.4
Cost584
\[\begin{array}{l} t_0 := x + \frac{1}{y}\\ \mathbf{if}\;y \leq -564.3173039255272:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq 2.974344203570807 \cdot 10^{-8}:\\ \;\;\;\;1 + y \cdot x\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \]
Alternative 8
Error16.4
Cost456
\[\begin{array}{l} \mathbf{if}\;y \leq -564.3173039255272:\\ \;\;\;\;x\\ \mathbf{elif}\;y \leq 2.974344203570807 \cdot 10^{-8}:\\ \;\;\;\;1 - y\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \]
Alternative 9
Error16.5
Cost328
\[\begin{array}{l} \mathbf{if}\;y \leq -564.3173039255272:\\ \;\;\;\;x\\ \mathbf{elif}\;y \leq 2.974344203570807 \cdot 10^{-8}:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \]
Alternative 10
Error38.9
Cost64
\[x \]

Error

Reproduce

herbie shell --seed 2022310 
(FPCore (x y)
  :name "Diagrams.Trail:splitAtParam  from diagrams-lib-1.3.0.3, D"
  :precision binary64

  :herbie-target
  (if (< y -3693.8482788297247) (- (/ 1.0 y) (- (/ x y) x)) (if (< y 6799310503.41891) (- 1.0 (/ (* (- 1.0 x) y) (+ y 1.0))) (- (/ 1.0 y) (- (/ x y) x))))

  (- 1.0 (/ (* (- 1.0 x) y) (+ y 1.0))))