
(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 99.9%
add-cbrt-cube99.9%
pow3100.0%
Applied egg-rr100.0%
rem-cbrt-cube99.9%
*-un-lft-identity99.9%
associate-*l/99.7%
distribute-lft-in99.7%
flip-+99.7%
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%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (x y) :precision binary64 (if (or (<= x -4.6e-7) (not (<= x 4.9e+58))) (+ 1.0 (* 2.0 (/ y x))) -1.0))
double code(double x, double y) {
double tmp;
if ((x <= -4.6e-7) || !(x <= 4.9e+58)) {
tmp = 1.0 + (2.0 * (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 <= (-4.6d-7)) .or. (.not. (x <= 4.9d+58))) then
tmp = 1.0d0 + (2.0d0 * (y / x))
else
tmp = -1.0d0
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((x <= -4.6e-7) || !(x <= 4.9e+58)) {
tmp = 1.0 + (2.0 * (y / x));
} else {
tmp = -1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -4.6e-7) or not (x <= 4.9e+58): tmp = 1.0 + (2.0 * (y / x)) else: tmp = -1.0 return tmp
function code(x, y) tmp = 0.0 if ((x <= -4.6e-7) || !(x <= 4.9e+58)) tmp = Float64(1.0 + Float64(2.0 * Float64(y / x))); else tmp = -1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((x <= -4.6e-7) || ~((x <= 4.9e+58))) tmp = 1.0 + (2.0 * (y / x)); else tmp = -1.0; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -4.6e-7], N[Not[LessEqual[x, 4.9e+58]], $MachinePrecision]], N[(1.0 + N[(2.0 * N[(y / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1.0]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -4.6 \cdot 10^{-7} \lor \neg \left(x \leq 4.9 \cdot 10^{+58}\right):\\
\;\;\;\;1 + 2 \cdot \frac{y}{x}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if x < -4.5999999999999999e-7 or 4.90000000000000018e58 < x Initial program 99.9%
Taylor expanded in y around 0 78.9%
if -4.5999999999999999e-7 < x < 4.90000000000000018e58Initial program 99.9%
Taylor expanded in x around 0 75.6%
Final simplification76.9%
(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 99.9%
Final simplification99.9%
(FPCore (x y) :precision binary64 (if (<= x -5e+33) 1.0 (if (<= x 1.4e+59) -1.0 1.0)))
double code(double x, double y) {
double tmp;
if (x <= -5e+33) {
tmp = 1.0;
} else if (x <= 1.4e+59) {
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 <= (-5d+33)) then
tmp = 1.0d0
else if (x <= 1.4d+59) 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 <= -5e+33) {
tmp = 1.0;
} else if (x <= 1.4e+59) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -5e+33: tmp = 1.0 elif x <= 1.4e+59: tmp = -1.0 else: tmp = 1.0 return tmp
function code(x, y) tmp = 0.0 if (x <= -5e+33) tmp = 1.0; elseif (x <= 1.4e+59) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -5e+33) tmp = 1.0; elseif (x <= 1.4e+59) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -5e+33], 1.0, If[LessEqual[x, 1.4e+59], -1.0, 1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -5 \cdot 10^{+33}:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 1.4 \cdot 10^{+59}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -4.99999999999999973e33 or 1.3999999999999999e59 < x Initial program 99.9%
Taylor expanded in x around inf 80.1%
if -4.99999999999999973e33 < x < 1.3999999999999999e59Initial program 99.9%
Taylor expanded in x around 0 74.3%
Final simplification76.5%
(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 99.9%
Taylor expanded in x around 0 53.8%
Final simplification53.8%
(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 2023238
(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)))