
(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 (/ (+ 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%
(FPCore (x y) :precision binary64 (if (or (<= y -5.2e+60) (not (<= y 1.55e+15))) (+ (* -2.0 (/ x y)) -1.0) (+ 1.0 (* 2.0 (/ y x)))))
double code(double x, double y) {
double tmp;
if ((y <= -5.2e+60) || !(y <= 1.55e+15)) {
tmp = (-2.0 * (x / y)) + -1.0;
} else {
tmp = 1.0 + (2.0 * (y / x));
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if ((y <= (-5.2d+60)) .or. (.not. (y <= 1.55d+15))) then
tmp = ((-2.0d0) * (x / y)) + (-1.0d0)
else
tmp = 1.0d0 + (2.0d0 * (y / x))
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((y <= -5.2e+60) || !(y <= 1.55e+15)) {
tmp = (-2.0 * (x / y)) + -1.0;
} else {
tmp = 1.0 + (2.0 * (y / x));
}
return tmp;
}
def code(x, y): tmp = 0 if (y <= -5.2e+60) or not (y <= 1.55e+15): tmp = (-2.0 * (x / y)) + -1.0 else: tmp = 1.0 + (2.0 * (y / x)) return tmp
function code(x, y) tmp = 0.0 if ((y <= -5.2e+60) || !(y <= 1.55e+15)) tmp = Float64(Float64(-2.0 * Float64(x / y)) + -1.0); else tmp = Float64(1.0 + Float64(2.0 * Float64(y / x))); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((y <= -5.2e+60) || ~((y <= 1.55e+15))) tmp = (-2.0 * (x / y)) + -1.0; else tmp = 1.0 + (2.0 * (y / x)); end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[y, -5.2e+60], N[Not[LessEqual[y, 1.55e+15]], $MachinePrecision]], N[(N[(-2.0 * N[(x / y), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision], N[(1.0 + N[(2.0 * N[(y / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -5.2 \cdot 10^{+60} \lor \neg \left(y \leq 1.55 \cdot 10^{+15}\right):\\
\;\;\;\;-2 \cdot \frac{x}{y} + -1\\
\mathbf{else}:\\
\;\;\;\;1 + 2 \cdot \frac{y}{x}\\
\end{array}
\end{array}
if y < -5.20000000000000016e60 or 1.55e15 < y Initial program 100.0%
Taylor expanded in x around 0 85.8%
if -5.20000000000000016e60 < y < 1.55e15Initial program 99.9%
Taylor expanded in y around 0 81.7%
Final simplification83.6%
(FPCore (x y) :precision binary64 (if (<= y -9.2e+52) -1.0 (if (<= y 2.1e+14) (+ 1.0 (* 2.0 (/ y x))) -1.0)))
double code(double x, double y) {
double tmp;
if (y <= -9.2e+52) {
tmp = -1.0;
} else if (y <= 2.1e+14) {
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 (y <= (-9.2d+52)) then
tmp = -1.0d0
else if (y <= 2.1d+14) 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 (y <= -9.2e+52) {
tmp = -1.0;
} else if (y <= 2.1e+14) {
tmp = 1.0 + (2.0 * (y / x));
} else {
tmp = -1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -9.2e+52: tmp = -1.0 elif y <= 2.1e+14: tmp = 1.0 + (2.0 * (y / x)) else: tmp = -1.0 return tmp
function code(x, y) tmp = 0.0 if (y <= -9.2e+52) tmp = -1.0; elseif (y <= 2.1e+14) 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 (y <= -9.2e+52) tmp = -1.0; elseif (y <= 2.1e+14) tmp = 1.0 + (2.0 * (y / x)); else tmp = -1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, -9.2e+52], -1.0, If[LessEqual[y, 2.1e+14], N[(1.0 + N[(2.0 * N[(y / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -9.2 \cdot 10^{+52}:\\
\;\;\;\;-1\\
\mathbf{elif}\;y \leq 2.1 \cdot 10^{+14}:\\
\;\;\;\;1 + 2 \cdot \frac{y}{x}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if y < -9.1999999999999999e52 or 2.1e14 < y Initial program 100.0%
Taylor expanded in x around 0 84.0%
if -9.1999999999999999e52 < y < 2.1e14Initial program 99.9%
Taylor expanded in y around 0 82.1%
(FPCore (x y) :precision binary64 (if (<= y -4.6e+65) -1.0 (if (<= y 7.5e+17) 1.0 -1.0)))
double code(double x, double y) {
double tmp;
if (y <= -4.6e+65) {
tmp = -1.0;
} else if (y <= 7.5e+17) {
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 (y <= (-4.6d+65)) then
tmp = -1.0d0
else if (y <= 7.5d+17) 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 (y <= -4.6e+65) {
tmp = -1.0;
} else if (y <= 7.5e+17) {
tmp = 1.0;
} else {
tmp = -1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -4.6e+65: tmp = -1.0 elif y <= 7.5e+17: tmp = 1.0 else: tmp = -1.0 return tmp
function code(x, y) tmp = 0.0 if (y <= -4.6e+65) tmp = -1.0; elseif (y <= 7.5e+17) tmp = 1.0; else tmp = -1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (y <= -4.6e+65) tmp = -1.0; elseif (y <= 7.5e+17) tmp = 1.0; else tmp = -1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, -4.6e+65], -1.0, If[LessEqual[y, 7.5e+17], 1.0, -1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -4.6 \cdot 10^{+65}:\\
\;\;\;\;-1\\
\mathbf{elif}\;y \leq 7.5 \cdot 10^{+17}:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if y < -4.6e65 or 7.5e17 < y Initial program 100.0%
Taylor expanded in x around 0 85.2%
if -4.6e65 < y < 7.5e17Initial program 99.9%
Taylor expanded in x around inf 80.1%
(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 49.5%
(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 2024087
(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)))