
(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 99.9%
Final simplification99.9%
(FPCore (x y) :precision binary64 (if (or (<= x -2.1e+19) (not (<= x 2.75e-14))) (+ 1.0 (* -2.0 (/ y x))) -1.0))
double code(double x, double y) {
double tmp;
if ((x <= -2.1e+19) || !(x <= 2.75e-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 ((x <= (-2.1d+19)) .or. (.not. (x <= 2.75d-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 ((x <= -2.1e+19) || !(x <= 2.75e-14)) {
tmp = 1.0 + (-2.0 * (y / x));
} else {
tmp = -1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -2.1e+19) or not (x <= 2.75e-14): tmp = 1.0 + (-2.0 * (y / x)) else: tmp = -1.0 return tmp
function code(x, y) tmp = 0.0 if ((x <= -2.1e+19) || !(x <= 2.75e-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 ((x <= -2.1e+19) || ~((x <= 2.75e-14))) tmp = 1.0 + (-2.0 * (y / x)); else tmp = -1.0; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -2.1e+19], N[Not[LessEqual[x, 2.75e-14]], $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 -2.1 \cdot 10^{+19} \lor \neg \left(x \leq 2.75 \cdot 10^{-14}\right):\\
\;\;\;\;1 + -2 \cdot \frac{y}{x}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if x < -2.1e19 or 2.74999999999999996e-14 < x Initial program 99.9%
Taylor expanded in y around 0 79.1%
if -2.1e19 < x < 2.74999999999999996e-14Initial program 99.9%
Taylor expanded in x around 0 81.5%
Final simplification80.3%
(FPCore (x y) :precision binary64 (if (or (<= x -6e+19) (not (<= x 2.75e-14))) (+ 1.0 (* -2.0 (/ y x))) (+ (* 2.0 (/ x y)) -1.0)))
double code(double x, double y) {
double tmp;
if ((x <= -6e+19) || !(x <= 2.75e-14)) {
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 <= (-6d+19)) .or. (.not. (x <= 2.75d-14))) 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 <= -6e+19) || !(x <= 2.75e-14)) {
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 <= -6e+19) or not (x <= 2.75e-14): 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 <= -6e+19) || !(x <= 2.75e-14)) 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 <= -6e+19) || ~((x <= 2.75e-14))) 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, -6e+19], N[Not[LessEqual[x, 2.75e-14]], $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 -6 \cdot 10^{+19} \lor \neg \left(x \leq 2.75 \cdot 10^{-14}\right):\\
\;\;\;\;1 + -2 \cdot \frac{y}{x}\\
\mathbf{else}:\\
\;\;\;\;2 \cdot \frac{x}{y} + -1\\
\end{array}
\end{array}
if x < -6e19 or 2.74999999999999996e-14 < x Initial program 99.9%
Taylor expanded in y around 0 79.1%
if -6e19 < x < 2.74999999999999996e-14Initial program 99.9%
Taylor expanded in x around 0 82.6%
Final simplification80.9%
(FPCore (x y) :precision binary64 (if (<= x -4.8e+18) 1.0 (if (<= x 2.75e-14) -1.0 1.0)))
double code(double x, double y) {
double tmp;
if (x <= -4.8e+18) {
tmp = 1.0;
} else if (x <= 2.75e-14) {
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 <= (-4.8d+18)) then
tmp = 1.0d0
else if (x <= 2.75d-14) 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 <= -4.8e+18) {
tmp = 1.0;
} else if (x <= 2.75e-14) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -4.8e+18: tmp = 1.0 elif x <= 2.75e-14: tmp = -1.0 else: tmp = 1.0 return tmp
function code(x, y) tmp = 0.0 if (x <= -4.8e+18) tmp = 1.0; elseif (x <= 2.75e-14) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -4.8e+18) tmp = 1.0; elseif (x <= 2.75e-14) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -4.8e+18], 1.0, If[LessEqual[x, 2.75e-14], -1.0, 1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -4.8 \cdot 10^{+18}:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 2.75 \cdot 10^{-14}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -4.8e18 or 2.74999999999999996e-14 < x Initial program 99.9%
Taylor expanded in x around inf 78.3%
if -4.8e18 < x < 2.74999999999999996e-14Initial program 99.9%
Taylor expanded in x around 0 81.5%
Final simplification79.9%
(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 51.6%
Final simplification51.6%
(FPCore (x y) :precision binary64 (- (/ x (+ x y)) (/ y (+ x y))))
double code(double x, double y) {
return (x / (x + y)) - (y / (x + y));
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (x / (x + y)) - (y / (x + y))
end function
public static double code(double x, double y) {
return (x / (x + y)) - (y / (x + y));
}
def code(x, y): return (x / (x + y)) - (y / (x + y))
function code(x, y) return Float64(Float64(x / Float64(x + y)) - Float64(y / Float64(x + y))) end
function tmp = code(x, y) tmp = (x / (x + y)) - (y / (x + y)); end
code[x_, y_] := N[(N[(x / N[(x + y), $MachinePrecision]), $MachinePrecision] - N[(y / N[(x + y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{x}{x + y} - \frac{y}{x + y}
\end{array}
herbie shell --seed 2023230
(FPCore (x y)
:name "Data.Colour.RGB:hslsv from colour-2.3.3, D"
:precision binary64
:herbie-target
(- (/ x (+ x y)) (/ y (+ x y)))
(/ (- x y) (+ x y)))