
(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:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(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}
(FPCore (x y) :precision binary64 (let* ((t_0 (/ x (- x y))) (t_1 (/ y (- x y)))) (/ (- (* t_0 t_0) (* t_1 t_1)) (- t_0 t_1))))
double code(double x, double y) {
double t_0 = x / (x - y);
double t_1 = y / (x - y);
return ((t_0 * t_0) - (t_1 * t_1)) / (t_0 - t_1);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: t_0
real(8) :: t_1
t_0 = x / (x - y)
t_1 = y / (x - y)
code = ((t_0 * t_0) - (t_1 * t_1)) / (t_0 - t_1)
end function
public static double code(double x, double y) {
double t_0 = x / (x - y);
double t_1 = y / (x - y);
return ((t_0 * t_0) - (t_1 * t_1)) / (t_0 - t_1);
}
def code(x, y): t_0 = x / (x - y) t_1 = y / (x - y) return ((t_0 * t_0) - (t_1 * t_1)) / (t_0 - t_1)
function code(x, y) t_0 = Float64(x / Float64(x - y)) t_1 = Float64(y / Float64(x - y)) return Float64(Float64(Float64(t_0 * t_0) - Float64(t_1 * t_1)) / Float64(t_0 - t_1)) end
function tmp = code(x, y) t_0 = x / (x - y); t_1 = y / (x - y); tmp = ((t_0 * t_0) - (t_1 * t_1)) / (t_0 - t_1); end
code[x_, y_] := Block[{t$95$0 = N[(x / N[(x - y), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(y / N[(x - y), $MachinePrecision]), $MachinePrecision]}, N[(N[(N[(t$95$0 * t$95$0), $MachinePrecision] - N[(t$95$1 * t$95$1), $MachinePrecision]), $MachinePrecision] / N[(t$95$0 - t$95$1), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{x}{x - y}\\
t_1 := \frac{y}{x - y}\\
\frac{t_0 \cdot t_0 - t_1 \cdot t_1}{t_0 - t_1}
\end{array}
\end{array}
Initial program 100.0%
clear-num100.0%
associate-/r/99.8%
Applied egg-rr99.8%
distribute-lft-in99.7%
flip-+99.8%
associate-*l/99.8%
*-un-lft-identity99.8%
associate-*l/99.7%
*-un-lft-identity99.7%
associate-*l/99.9%
*-un-lft-identity99.9%
associate-*l/99.7%
*-un-lft-identity99.7%
associate-*l/99.8%
*-un-lft-identity99.8%
associate-*l/100.0%
*-un-lft-identity100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (x y) :precision binary64 (/ 1.0 (/ (- x y) (+ x y))))
double code(double x, double y) {
return 1.0 / ((x - y) / (x + y));
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = 1.0d0 / ((x - y) / (x + y))
end function
public static double code(double x, double y) {
return 1.0 / ((x - y) / (x + y));
}
def code(x, y): return 1.0 / ((x - y) / (x + y))
function code(x, y) return Float64(1.0 / Float64(Float64(x - y) / Float64(x + y))) end
function tmp = code(x, y) tmp = 1.0 / ((x - y) / (x + y)); end
code[x_, y_] := N[(1.0 / N[(N[(x - y), $MachinePrecision] / N[(x + y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\frac{x - y}{x + y}}
\end{array}
Initial program 100.0%
clear-num100.0%
associate-/r/99.8%
Applied egg-rr99.8%
associate-/r/100.0%
Applied egg-rr100.0%
Final simplification100.0%
(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}
Initial program 100.0%
Final simplification100.0%
(FPCore (x y) :precision binary64 (if (<= x -1.52e+100) 1.0 (if (<= x 2e-77) -1.0 1.0)))
double code(double x, double y) {
double tmp;
if (x <= -1.52e+100) {
tmp = 1.0;
} else if (x <= 2e-77) {
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 <= (-1.52d+100)) then
tmp = 1.0d0
else if (x <= 2d-77) 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 <= -1.52e+100) {
tmp = 1.0;
} else if (x <= 2e-77) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -1.52e+100: tmp = 1.0 elif x <= 2e-77: tmp = -1.0 else: tmp = 1.0 return tmp
function code(x, y) tmp = 0.0 if (x <= -1.52e+100) tmp = 1.0; elseif (x <= 2e-77) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -1.52e+100) tmp = 1.0; elseif (x <= 2e-77) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -1.52e+100], 1.0, If[LessEqual[x, 2e-77], -1.0, 1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.52 \cdot 10^{+100}:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 2 \cdot 10^{-77}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -1.52e100 or 1.9999999999999999e-77 < x Initial program 100.0%
Taylor expanded in x around inf 81.3%
if -1.52e100 < x < 1.9999999999999999e-77Initial program 100.0%
Taylor expanded in x around 0 73.3%
Final simplification77.4%
(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}
Initial program 100.0%
Taylor expanded in x around 0 45.4%
Final simplification45.4%
(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}
herbie shell --seed 2023310
(FPCore (x y)
:name "Linear.Projection:perspective from linear-1.19.1.3, A"
:precision binary64
:herbie-target
(/ 1.0 (- (/ x (+ x y)) (/ y (+ x y))))
(/ (+ x y) (- x y)))