Linear.Projection:perspective from linear-1.19.1.3, A

Percentage Accurate: 100.0% → 100.0%
Time: 5.7s
Alternatives: 8
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \frac{x + y}{x - y} \end{array} \]
(FPCore (x y) :precision binary64 (/ (+ x y) (- x y)))
double code(double x, double y) {
	return (x + y) / (x - y);
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = (x + y) / (x - y)
end function
public static double code(double x, double y) {
	return (x + y) / (x - y);
}
def code(x, y):
	return (x + y) / (x - y)
function code(x, y)
	return Float64(Float64(x + y) / Float64(x - y))
end
function tmp = code(x, y)
	tmp = (x + y) / (x - y);
end
code[x_, y_] := N[(N[(x + y), $MachinePrecision] / N[(x - y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x + y}{x - y}
\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 8 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: 100.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{x + y}{x - y} \end{array} \]
(FPCore (x y) :precision binary64 (/ (+ x y) (- x y)))
double code(double x, double y) {
	return (x + y) / (x - y);
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = (x + y) / (x - y)
end function
public static double code(double x, double y) {
	return (x + y) / (x - y);
}
def code(x, y):
	return (x + y) / (x - y)
function code(x, y)
	return Float64(Float64(x + y) / Float64(x - y))
end
function tmp = code(x, y)
	tmp = (x + y) / (x - y);
end
code[x_, y_] := N[(N[(x + y), $MachinePrecision] / N[(x - y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x + y}{x - y}
\end{array}

Alternative 1: 100.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{x + y}{x - y} \end{array} \]
(FPCore (x y) :precision binary64 (/ (+ x y) (- x y)))
double code(double x, double y) {
	return (x + y) / (x - y);
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = (x + y) / (x - y)
end function
public static double code(double x, double y) {
	return (x + y) / (x - y);
}
def code(x, y):
	return (x + y) / (x - y)
function code(x, y)
	return Float64(Float64(x + y) / Float64(x - y))
end
function tmp = code(x, y)
	tmp = (x + y) / (x - y);
end
code[x_, y_] := N[(N[(x + y), $MachinePrecision] / N[(x - y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x + y}{x - y}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{x + y}{x - y} \]
  2. Add Preprocessing
  3. Add Preprocessing

Alternative 2: 74.8% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -5.5 \cdot 10^{+29} \lor \neg \left(x \leq 4.1 \cdot 10^{-88}\right) \land \left(x \leq 7.8 \cdot 10^{-46} \lor \neg \left(x \leq 70000\right)\right):\\ \;\;\;\;1 + 2 \cdot \frac{y}{x}\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot \frac{x}{y} + -1\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (or (<= x -5.5e+29)
         (and (not (<= x 4.1e-88)) (or (<= x 7.8e-46) (not (<= x 70000.0)))))
   (+ 1.0 (* 2.0 (/ y x)))
   (+ (* -2.0 (/ x y)) -1.0)))
double code(double x, double y) {
	double tmp;
	if ((x <= -5.5e+29) || (!(x <= 4.1e-88) && ((x <= 7.8e-46) || !(x <= 70000.0)))) {
		tmp = 1.0 + (2.0 * (y / x));
	} else {
		tmp = (-2.0 * (x / y)) + -1.0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if ((x <= (-5.5d+29)) .or. (.not. (x <= 4.1d-88)) .and. (x <= 7.8d-46) .or. (.not. (x <= 70000.0d0))) then
        tmp = 1.0d0 + (2.0d0 * (y / x))
    else
        tmp = ((-2.0d0) * (x / y)) + (-1.0d0)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if ((x <= -5.5e+29) || (!(x <= 4.1e-88) && ((x <= 7.8e-46) || !(x <= 70000.0)))) {
		tmp = 1.0 + (2.0 * (y / x));
	} else {
		tmp = (-2.0 * (x / y)) + -1.0;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if (x <= -5.5e+29) or (not (x <= 4.1e-88) and ((x <= 7.8e-46) or not (x <= 70000.0))):
		tmp = 1.0 + (2.0 * (y / x))
	else:
		tmp = (-2.0 * (x / y)) + -1.0
	return tmp
function code(x, y)
	tmp = 0.0
	if ((x <= -5.5e+29) || (!(x <= 4.1e-88) && ((x <= 7.8e-46) || !(x <= 70000.0))))
		tmp = Float64(1.0 + Float64(2.0 * Float64(y / x)));
	else
		tmp = Float64(Float64(-2.0 * Float64(x / y)) + -1.0);
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if ((x <= -5.5e+29) || (~((x <= 4.1e-88)) && ((x <= 7.8e-46) || ~((x <= 70000.0)))))
		tmp = 1.0 + (2.0 * (y / x));
	else
		tmp = (-2.0 * (x / y)) + -1.0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[Or[LessEqual[x, -5.5e+29], And[N[Not[LessEqual[x, 4.1e-88]], $MachinePrecision], Or[LessEqual[x, 7.8e-46], N[Not[LessEqual[x, 70000.0]], $MachinePrecision]]]], N[(1.0 + N[(2.0 * N[(y / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(-2.0 * N[(x / y), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -5.5 \cdot 10^{+29} \lor \neg \left(x \leq 4.1 \cdot 10^{-88}\right) \land \left(x \leq 7.8 \cdot 10^{-46} \lor \neg \left(x \leq 70000\right)\right):\\
\;\;\;\;1 + 2 \cdot \frac{y}{x}\\

\mathbf{else}:\\
\;\;\;\;-2 \cdot \frac{x}{y} + -1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -5.5e29 or 4.1000000000000001e-88 < x < 7.8000000000000005e-46 or 7e4 < x

    1. Initial program 100.0%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in y around 0 80.0%

      \[\leadsto \color{blue}{1 + 2 \cdot \frac{y}{x}} \]

    if -5.5e29 < x < 4.1000000000000001e-88 or 7.8000000000000005e-46 < x < 7e4

    1. Initial program 99.9%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 80.2%

      \[\leadsto \color{blue}{-2 \cdot \frac{x}{y} - 1} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification80.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -5.5 \cdot 10^{+29} \lor \neg \left(x \leq 4.1 \cdot 10^{-88}\right) \land \left(x \leq 7.8 \cdot 10^{-46} \lor \neg \left(x \leq 70000\right)\right):\\ \;\;\;\;1 + 2 \cdot \frac{y}{x}\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot \frac{x}{y} + -1\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 74.6% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + 2 \cdot \frac{y}{x}\\ t_1 := \frac{y}{x - y}\\ \mathbf{if}\;x \leq -6.8 \cdot 10^{+23}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;x \leq 8 \cdot 10^{-77}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;x \leq 7 \cdot 10^{-46}:\\ \;\;\;\;\frac{x}{x - y}\\ \mathbf{elif}\;x \leq 24000:\\ \;\;\;\;t\_1\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (+ 1.0 (* 2.0 (/ y x)))) (t_1 (/ y (- x y))))
   (if (<= x -6.8e+23)
     t_0
     (if (<= x 8e-77)
       t_1
       (if (<= x 7e-46) (/ x (- x y)) (if (<= x 24000.0) t_1 t_0))))))
double code(double x, double y) {
	double t_0 = 1.0 + (2.0 * (y / x));
	double t_1 = y / (x - y);
	double tmp;
	if (x <= -6.8e+23) {
		tmp = t_0;
	} else if (x <= 8e-77) {
		tmp = t_1;
	} else if (x <= 7e-46) {
		tmp = x / (x - y);
	} else if (x <= 24000.0) {
		tmp = t_1;
	} else {
		tmp = t_0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: tmp
    t_0 = 1.0d0 + (2.0d0 * (y / x))
    t_1 = y / (x - y)
    if (x <= (-6.8d+23)) then
        tmp = t_0
    else if (x <= 8d-77) then
        tmp = t_1
    else if (x <= 7d-46) then
        tmp = x / (x - y)
    else if (x <= 24000.0d0) then
        tmp = t_1
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double t_0 = 1.0 + (2.0 * (y / x));
	double t_1 = y / (x - y);
	double tmp;
	if (x <= -6.8e+23) {
		tmp = t_0;
	} else if (x <= 8e-77) {
		tmp = t_1;
	} else if (x <= 7e-46) {
		tmp = x / (x - y);
	} else if (x <= 24000.0) {
		tmp = t_1;
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = 1.0 + (2.0 * (y / x))
	t_1 = y / (x - y)
	tmp = 0
	if x <= -6.8e+23:
		tmp = t_0
	elif x <= 8e-77:
		tmp = t_1
	elif x <= 7e-46:
		tmp = x / (x - y)
	elif x <= 24000.0:
		tmp = t_1
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(1.0 + Float64(2.0 * Float64(y / x)))
	t_1 = Float64(y / Float64(x - y))
	tmp = 0.0
	if (x <= -6.8e+23)
		tmp = t_0;
	elseif (x <= 8e-77)
		tmp = t_1;
	elseif (x <= 7e-46)
		tmp = Float64(x / Float64(x - y));
	elseif (x <= 24000.0)
		tmp = t_1;
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = 1.0 + (2.0 * (y / x));
	t_1 = y / (x - y);
	tmp = 0.0;
	if (x <= -6.8e+23)
		tmp = t_0;
	elseif (x <= 8e-77)
		tmp = t_1;
	elseif (x <= 7e-46)
		tmp = x / (x - y);
	elseif (x <= 24000.0)
		tmp = t_1;
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[(1.0 + N[(2.0 * N[(y / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(y / N[(x - y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, -6.8e+23], t$95$0, If[LessEqual[x, 8e-77], t$95$1, If[LessEqual[x, 7e-46], N[(x / N[(x - y), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 24000.0], t$95$1, t$95$0]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 + 2 \cdot \frac{y}{x}\\
t_1 := \frac{y}{x - y}\\
\mathbf{if}\;x \leq -6.8 \cdot 10^{+23}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;x \leq 8 \cdot 10^{-77}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;x \leq 7 \cdot 10^{-46}:\\
\;\;\;\;\frac{x}{x - y}\\

\mathbf{elif}\;x \leq 24000:\\
\;\;\;\;t\_1\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -6.79999999999999983e23 or 24000 < x

    1. Initial program 100.0%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in y around 0 81.3%

      \[\leadsto \color{blue}{1 + 2 \cdot \frac{y}{x}} \]

    if -6.79999999999999983e23 < x < 7.9999999999999994e-77 or 7.0000000000000004e-46 < x < 24000

    1. Initial program 99.9%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 78.9%

      \[\leadsto \frac{\color{blue}{y}}{x - y} \]

    if 7.9999999999999994e-77 < x < 7.0000000000000004e-46

    1. Initial program 99.9%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf 77.8%

      \[\leadsto \frac{\color{blue}{x}}{x - y} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 4: 73.9% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -5.6 \cdot 10^{+25} \lor \neg \left(x \leq 4.1 \cdot 10^{-88}\right) \land \left(x \leq 7 \cdot 10^{-46} \lor \neg \left(x \leq 37000\right)\right):\\ \;\;\;\;1 + \frac{y}{x}\\ \mathbf{else}:\\ \;\;\;\;-1\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (or (<= x -5.6e+25)
         (and (not (<= x 4.1e-88)) (or (<= x 7e-46) (not (<= x 37000.0)))))
   (+ 1.0 (/ y x))
   -1.0))
double code(double x, double y) {
	double tmp;
	if ((x <= -5.6e+25) || (!(x <= 4.1e-88) && ((x <= 7e-46) || !(x <= 37000.0)))) {
		tmp = 1.0 + (y / x);
	} else {
		tmp = -1.0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if ((x <= (-5.6d+25)) .or. (.not. (x <= 4.1d-88)) .and. (x <= 7d-46) .or. (.not. (x <= 37000.0d0))) then
        tmp = 1.0d0 + (y / x)
    else
        tmp = -1.0d0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if ((x <= -5.6e+25) || (!(x <= 4.1e-88) && ((x <= 7e-46) || !(x <= 37000.0)))) {
		tmp = 1.0 + (y / x);
	} else {
		tmp = -1.0;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if (x <= -5.6e+25) or (not (x <= 4.1e-88) and ((x <= 7e-46) or not (x <= 37000.0))):
		tmp = 1.0 + (y / x)
	else:
		tmp = -1.0
	return tmp
function code(x, y)
	tmp = 0.0
	if ((x <= -5.6e+25) || (!(x <= 4.1e-88) && ((x <= 7e-46) || !(x <= 37000.0))))
		tmp = Float64(1.0 + Float64(y / x));
	else
		tmp = -1.0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if ((x <= -5.6e+25) || (~((x <= 4.1e-88)) && ((x <= 7e-46) || ~((x <= 37000.0)))))
		tmp = 1.0 + (y / x);
	else
		tmp = -1.0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[Or[LessEqual[x, -5.6e+25], And[N[Not[LessEqual[x, 4.1e-88]], $MachinePrecision], Or[LessEqual[x, 7e-46], N[Not[LessEqual[x, 37000.0]], $MachinePrecision]]]], N[(1.0 + N[(y / x), $MachinePrecision]), $MachinePrecision], -1.0]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -5.6 \cdot 10^{+25} \lor \neg \left(x \leq 4.1 \cdot 10^{-88}\right) \land \left(x \leq 7 \cdot 10^{-46} \lor \neg \left(x \leq 37000\right)\right):\\
\;\;\;\;1 + \frac{y}{x}\\

\mathbf{else}:\\
\;\;\;\;-1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -5.6000000000000003e25 or 4.1000000000000001e-88 < x < 7.0000000000000004e-46 or 37000 < x

    1. Initial program 100.0%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf 79.1%

      \[\leadsto \frac{\color{blue}{x}}{x - y} \]
    4. Taylor expanded in x around inf 79.3%

      \[\leadsto \color{blue}{1 + \frac{y}{x}} \]

    if -5.6000000000000003e25 < x < 4.1000000000000001e-88 or 7.0000000000000004e-46 < x < 37000

    1. Initial program 99.9%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 78.8%

      \[\leadsto \color{blue}{-1} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification79.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -5.6 \cdot 10^{+25} \lor \neg \left(x \leq 4.1 \cdot 10^{-88}\right) \land \left(x \leq 7 \cdot 10^{-46} \lor \neg \left(x \leq 37000\right)\right):\\ \;\;\;\;1 + \frac{y}{x}\\ \mathbf{else}:\\ \;\;\;\;-1\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 74.4% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + \frac{y}{x}\\ t_1 := \frac{y}{x - y}\\ \mathbf{if}\;x \leq -2.3 \cdot 10^{+31}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;x \leq 7.2 \cdot 10^{-77}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;x \leq 6.8 \cdot 10^{-46}:\\ \;\;\;\;\frac{x}{x - y}\\ \mathbf{elif}\;x \leq 180000:\\ \;\;\;\;t\_1\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (+ 1.0 (/ y x))) (t_1 (/ y (- x y))))
   (if (<= x -2.3e+31)
     t_0
     (if (<= x 7.2e-77)
       t_1
       (if (<= x 6.8e-46) (/ x (- x y)) (if (<= x 180000.0) t_1 t_0))))))
double code(double x, double y) {
	double t_0 = 1.0 + (y / x);
	double t_1 = y / (x - y);
	double tmp;
	if (x <= -2.3e+31) {
		tmp = t_0;
	} else if (x <= 7.2e-77) {
		tmp = t_1;
	} else if (x <= 6.8e-46) {
		tmp = x / (x - y);
	} else if (x <= 180000.0) {
		tmp = t_1;
	} else {
		tmp = t_0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: tmp
    t_0 = 1.0d0 + (y / x)
    t_1 = y / (x - y)
    if (x <= (-2.3d+31)) then
        tmp = t_0
    else if (x <= 7.2d-77) then
        tmp = t_1
    else if (x <= 6.8d-46) then
        tmp = x / (x - y)
    else if (x <= 180000.0d0) then
        tmp = t_1
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double t_0 = 1.0 + (y / x);
	double t_1 = y / (x - y);
	double tmp;
	if (x <= -2.3e+31) {
		tmp = t_0;
	} else if (x <= 7.2e-77) {
		tmp = t_1;
	} else if (x <= 6.8e-46) {
		tmp = x / (x - y);
	} else if (x <= 180000.0) {
		tmp = t_1;
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = 1.0 + (y / x)
	t_1 = y / (x - y)
	tmp = 0
	if x <= -2.3e+31:
		tmp = t_0
	elif x <= 7.2e-77:
		tmp = t_1
	elif x <= 6.8e-46:
		tmp = x / (x - y)
	elif x <= 180000.0:
		tmp = t_1
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(1.0 + Float64(y / x))
	t_1 = Float64(y / Float64(x - y))
	tmp = 0.0
	if (x <= -2.3e+31)
		tmp = t_0;
	elseif (x <= 7.2e-77)
		tmp = t_1;
	elseif (x <= 6.8e-46)
		tmp = Float64(x / Float64(x - y));
	elseif (x <= 180000.0)
		tmp = t_1;
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = 1.0 + (y / x);
	t_1 = y / (x - y);
	tmp = 0.0;
	if (x <= -2.3e+31)
		tmp = t_0;
	elseif (x <= 7.2e-77)
		tmp = t_1;
	elseif (x <= 6.8e-46)
		tmp = x / (x - y);
	elseif (x <= 180000.0)
		tmp = t_1;
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[(1.0 + N[(y / x), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(y / N[(x - y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, -2.3e+31], t$95$0, If[LessEqual[x, 7.2e-77], t$95$1, If[LessEqual[x, 6.8e-46], N[(x / N[(x - y), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 180000.0], t$95$1, t$95$0]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 + \frac{y}{x}\\
t_1 := \frac{y}{x - y}\\
\mathbf{if}\;x \leq -2.3 \cdot 10^{+31}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;x \leq 7.2 \cdot 10^{-77}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;x \leq 6.8 \cdot 10^{-46}:\\
\;\;\;\;\frac{x}{x - y}\\

\mathbf{elif}\;x \leq 180000:\\
\;\;\;\;t\_1\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -2.3e31 or 1.8e5 < x

    1. Initial program 100.0%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf 80.3%

      \[\leadsto \frac{\color{blue}{x}}{x - y} \]
    4. Taylor expanded in x around inf 80.6%

      \[\leadsto \color{blue}{1 + \frac{y}{x}} \]

    if -2.3e31 < x < 7.2e-77 or 6.79999999999999992e-46 < x < 1.8e5

    1. Initial program 99.9%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 78.9%

      \[\leadsto \frac{\color{blue}{y}}{x - y} \]

    if 7.2e-77 < x < 6.79999999999999992e-46

    1. Initial program 99.9%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf 77.8%

      \[\leadsto \frac{\color{blue}{x}}{x - y} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 6: 74.0% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + \frac{y}{x}\\ \mathbf{if}\;x \leq -3.4 \cdot 10^{+24}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;x \leq 4.2 \cdot 10^{-88}:\\ \;\;\;\;-1\\ \mathbf{elif}\;x \leq 7 \cdot 10^{-46}:\\ \;\;\;\;\frac{x}{x - y}\\ \mathbf{elif}\;x \leq 800000:\\ \;\;\;\;-1\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (+ 1.0 (/ y x))))
   (if (<= x -3.4e+24)
     t_0
     (if (<= x 4.2e-88)
       -1.0
       (if (<= x 7e-46) (/ x (- x y)) (if (<= x 800000.0) -1.0 t_0))))))
double code(double x, double y) {
	double t_0 = 1.0 + (y / x);
	double tmp;
	if (x <= -3.4e+24) {
		tmp = t_0;
	} else if (x <= 4.2e-88) {
		tmp = -1.0;
	} else if (x <= 7e-46) {
		tmp = x / (x - y);
	} else if (x <= 800000.0) {
		tmp = -1.0;
	} else {
		tmp = t_0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: t_0
    real(8) :: tmp
    t_0 = 1.0d0 + (y / x)
    if (x <= (-3.4d+24)) then
        tmp = t_0
    else if (x <= 4.2d-88) then
        tmp = -1.0d0
    else if (x <= 7d-46) then
        tmp = x / (x - y)
    else if (x <= 800000.0d0) then
        tmp = -1.0d0
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double t_0 = 1.0 + (y / x);
	double tmp;
	if (x <= -3.4e+24) {
		tmp = t_0;
	} else if (x <= 4.2e-88) {
		tmp = -1.0;
	} else if (x <= 7e-46) {
		tmp = x / (x - y);
	} else if (x <= 800000.0) {
		tmp = -1.0;
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = 1.0 + (y / x)
	tmp = 0
	if x <= -3.4e+24:
		tmp = t_0
	elif x <= 4.2e-88:
		tmp = -1.0
	elif x <= 7e-46:
		tmp = x / (x - y)
	elif x <= 800000.0:
		tmp = -1.0
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(1.0 + Float64(y / x))
	tmp = 0.0
	if (x <= -3.4e+24)
		tmp = t_0;
	elseif (x <= 4.2e-88)
		tmp = -1.0;
	elseif (x <= 7e-46)
		tmp = Float64(x / Float64(x - y));
	elseif (x <= 800000.0)
		tmp = -1.0;
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = 1.0 + (y / x);
	tmp = 0.0;
	if (x <= -3.4e+24)
		tmp = t_0;
	elseif (x <= 4.2e-88)
		tmp = -1.0;
	elseif (x <= 7e-46)
		tmp = x / (x - y);
	elseif (x <= 800000.0)
		tmp = -1.0;
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[(1.0 + N[(y / x), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, -3.4e+24], t$95$0, If[LessEqual[x, 4.2e-88], -1.0, If[LessEqual[x, 7e-46], N[(x / N[(x - y), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 800000.0], -1.0, t$95$0]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 + \frac{y}{x}\\
\mathbf{if}\;x \leq -3.4 \cdot 10^{+24}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;x \leq 4.2 \cdot 10^{-88}:\\
\;\;\;\;-1\\

\mathbf{elif}\;x \leq 7 \cdot 10^{-46}:\\
\;\;\;\;\frac{x}{x - y}\\

\mathbf{elif}\;x \leq 800000:\\
\;\;\;\;-1\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -3.4000000000000001e24 or 8e5 < x

    1. Initial program 100.0%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf 80.3%

      \[\leadsto \frac{\color{blue}{x}}{x - y} \]
    4. Taylor expanded in x around inf 80.6%

      \[\leadsto \color{blue}{1 + \frac{y}{x}} \]

    if -3.4000000000000001e24 < x < 4.1999999999999999e-88 or 7.0000000000000004e-46 < x < 8e5

    1. Initial program 99.9%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 78.8%

      \[\leadsto \color{blue}{-1} \]

    if 4.1999999999999999e-88 < x < 7.0000000000000004e-46

    1. Initial program 99.9%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf 71.2%

      \[\leadsto \frac{\color{blue}{x}}{x - y} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 7: 73.6% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -4 \cdot 10^{+27}:\\ \;\;\;\;1\\ \mathbf{elif}\;x \leq 4.1 \cdot 10^{-88}:\\ \;\;\;\;-1\\ \mathbf{elif}\;x \leq 7.8 \cdot 10^{-46}:\\ \;\;\;\;1\\ \mathbf{elif}\;x \leq 115000:\\ \;\;\;\;-1\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= x -4e+27)
   1.0
   (if (<= x 4.1e-88)
     -1.0
     (if (<= x 7.8e-46) 1.0 (if (<= x 115000.0) -1.0 1.0)))))
double code(double x, double y) {
	double tmp;
	if (x <= -4e+27) {
		tmp = 1.0;
	} else if (x <= 4.1e-88) {
		tmp = -1.0;
	} else if (x <= 7.8e-46) {
		tmp = 1.0;
	} else if (x <= 115000.0) {
		tmp = -1.0;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (x <= (-4d+27)) then
        tmp = 1.0d0
    else if (x <= 4.1d-88) then
        tmp = -1.0d0
    else if (x <= 7.8d-46) then
        tmp = 1.0d0
    else if (x <= 115000.0d0) then
        tmp = -1.0d0
    else
        tmp = 1.0d0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (x <= -4e+27) {
		tmp = 1.0;
	} else if (x <= 4.1e-88) {
		tmp = -1.0;
	} else if (x <= 7.8e-46) {
		tmp = 1.0;
	} else if (x <= 115000.0) {
		tmp = -1.0;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if x <= -4e+27:
		tmp = 1.0
	elif x <= 4.1e-88:
		tmp = -1.0
	elif x <= 7.8e-46:
		tmp = 1.0
	elif x <= 115000.0:
		tmp = -1.0
	else:
		tmp = 1.0
	return tmp
function code(x, y)
	tmp = 0.0
	if (x <= -4e+27)
		tmp = 1.0;
	elseif (x <= 4.1e-88)
		tmp = -1.0;
	elseif (x <= 7.8e-46)
		tmp = 1.0;
	elseif (x <= 115000.0)
		tmp = -1.0;
	else
		tmp = 1.0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (x <= -4e+27)
		tmp = 1.0;
	elseif (x <= 4.1e-88)
		tmp = -1.0;
	elseif (x <= 7.8e-46)
		tmp = 1.0;
	elseif (x <= 115000.0)
		tmp = -1.0;
	else
		tmp = 1.0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[x, -4e+27], 1.0, If[LessEqual[x, 4.1e-88], -1.0, If[LessEqual[x, 7.8e-46], 1.0, If[LessEqual[x, 115000.0], -1.0, 1.0]]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -4 \cdot 10^{+27}:\\
\;\;\;\;1\\

\mathbf{elif}\;x \leq 4.1 \cdot 10^{-88}:\\
\;\;\;\;-1\\

\mathbf{elif}\;x \leq 7.8 \cdot 10^{-46}:\\
\;\;\;\;1\\

\mathbf{elif}\;x \leq 115000:\\
\;\;\;\;-1\\

\mathbf{else}:\\
\;\;\;\;1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -4.0000000000000001e27 or 4.1000000000000001e-88 < x < 7.8000000000000005e-46 or 115000 < x

    1. Initial program 100.0%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf 78.6%

      \[\leadsto \color{blue}{1} \]

    if -4.0000000000000001e27 < x < 4.1000000000000001e-88 or 7.8000000000000005e-46 < x < 115000

    1. Initial program 99.9%

      \[\frac{x + y}{x - y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 78.8%

      \[\leadsto \color{blue}{-1} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 8: 49.2% accurate, 7.0× speedup?

\[\begin{array}{l} \\ -1 \end{array} \]
(FPCore (x y) :precision binary64 -1.0)
double code(double x, double y) {
	return -1.0;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = -1.0d0
end function
public static double code(double x, double y) {
	return -1.0;
}
def code(x, y):
	return -1.0
function code(x, y)
	return -1.0
end
function tmp = code(x, y)
	tmp = -1.0;
end
code[x_, y_] := -1.0
\begin{array}{l}

\\
-1
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{x + y}{x - y} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0 50.7%

    \[\leadsto \color{blue}{-1} \]
  4. Add Preprocessing

Developer target: 100.0% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \frac{1}{\frac{x}{x + y} - \frac{y}{x + y}} \end{array} \]
(FPCore (x y) :precision binary64 (/ 1.0 (- (/ x (+ x y)) (/ y (+ x y)))))
double code(double x, double y) {
	return 1.0 / ((x / (x + y)) - (y / (x + y)));
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = 1.0d0 / ((x / (x + y)) - (y / (x + y)))
end function
public static double code(double x, double y) {
	return 1.0 / ((x / (x + y)) - (y / (x + y)));
}
def code(x, y):
	return 1.0 / ((x / (x + y)) - (y / (x + y)))
function code(x, y)
	return Float64(1.0 / Float64(Float64(x / Float64(x + y)) - Float64(y / Float64(x + y))))
end
function tmp = code(x, y)
	tmp = 1.0 / ((x / (x + y)) - (y / (x + y)));
end
code[x_, y_] := N[(1.0 / N[(N[(x / N[(x + y), $MachinePrecision]), $MachinePrecision] - N[(y / N[(x + y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\frac{x}{x + y} - \frac{y}{x + y}}
\end{array}

Reproduce

?
herbie shell --seed 2024111 
(FPCore (x y)
  :name "Linear.Projection:perspective from linear-1.19.1.3, A"
  :precision binary64

  :alt
  (/ 1.0 (- (/ x (+ x y)) (/ y (+ x y))))

  (/ (+ x y) (- x y)))