
(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 4 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%
Final simplification100.0%
(FPCore (x y)
:precision binary64
(if (<= x -3.6e+129)
1.0
(if (or (<= x -4.8e-65) (and (not (<= x -3.6e-145)) (<= x 2.65e-14)))
(+ (* 2.0 (/ x y)) -1.0)
1.0)))
double code(double x, double y) {
double tmp;
if (x <= -3.6e+129) {
tmp = 1.0;
} else if ((x <= -4.8e-65) || (!(x <= -3.6e-145) && (x <= 2.65e-14))) {
tmp = (2.0 * (x / y)) + -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 <= (-3.6d+129)) then
tmp = 1.0d0
else if ((x <= (-4.8d-65)) .or. (.not. (x <= (-3.6d-145))) .and. (x <= 2.65d-14)) then
tmp = (2.0d0 * (x / y)) + (-1.0d0)
else
tmp = 1.0d0
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -3.6e+129) {
tmp = 1.0;
} else if ((x <= -4.8e-65) || (!(x <= -3.6e-145) && (x <= 2.65e-14))) {
tmp = (2.0 * (x / y)) + -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -3.6e+129: tmp = 1.0 elif (x <= -4.8e-65) or (not (x <= -3.6e-145) and (x <= 2.65e-14)): tmp = (2.0 * (x / y)) + -1.0 else: tmp = 1.0 return tmp
function code(x, y) tmp = 0.0 if (x <= -3.6e+129) tmp = 1.0; elseif ((x <= -4.8e-65) || (!(x <= -3.6e-145) && (x <= 2.65e-14))) tmp = Float64(Float64(2.0 * Float64(x / y)) + -1.0); else tmp = 1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -3.6e+129) tmp = 1.0; elseif ((x <= -4.8e-65) || (~((x <= -3.6e-145)) && (x <= 2.65e-14))) tmp = (2.0 * (x / y)) + -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -3.6e+129], 1.0, If[Or[LessEqual[x, -4.8e-65], And[N[Not[LessEqual[x, -3.6e-145]], $MachinePrecision], LessEqual[x, 2.65e-14]]], N[(N[(2.0 * N[(x / y), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision], 1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -3.6 \cdot 10^{+129}:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq -4.8 \cdot 10^{-65} \lor \neg \left(x \leq -3.6 \cdot 10^{-145}\right) \land x \leq 2.65 \cdot 10^{-14}:\\
\;\;\;\;2 \cdot \frac{x}{y} + -1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -3.6000000000000001e129 or -4.8000000000000003e-65 < x < -3.6e-145 or 2.6500000000000001e-14 < x Initial program 100.0%
Taylor expanded in x around inf 76.5%
if -3.6000000000000001e129 < x < -4.8000000000000003e-65 or -3.6e-145 < x < 2.6500000000000001e-14Initial program 100.0%
Taylor expanded in x around 0 81.0%
Final simplification78.7%
(FPCore (x y)
:precision binary64
(if (<= x -1e+84)
1.0
(if (<= x -3.5e-67)
-1.0
(if (<= x -1.65e-127) 1.0 (if (<= x 2.35e-17) -1.0 1.0)))))
double code(double x, double y) {
double tmp;
if (x <= -1e+84) {
tmp = 1.0;
} else if (x <= -3.5e-67) {
tmp = -1.0;
} else if (x <= -1.65e-127) {
tmp = 1.0;
} else if (x <= 2.35e-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 (x <= (-1d+84)) then
tmp = 1.0d0
else if (x <= (-3.5d-67)) then
tmp = -1.0d0
else if (x <= (-1.65d-127)) then
tmp = 1.0d0
else if (x <= 2.35d-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 (x <= -1e+84) {
tmp = 1.0;
} else if (x <= -3.5e-67) {
tmp = -1.0;
} else if (x <= -1.65e-127) {
tmp = 1.0;
} else if (x <= 2.35e-17) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -1e+84: tmp = 1.0 elif x <= -3.5e-67: tmp = -1.0 elif x <= -1.65e-127: tmp = 1.0 elif x <= 2.35e-17: tmp = -1.0 else: tmp = 1.0 return tmp
function code(x, y) tmp = 0.0 if (x <= -1e+84) tmp = 1.0; elseif (x <= -3.5e-67) tmp = -1.0; elseif (x <= -1.65e-127) tmp = 1.0; elseif (x <= 2.35e-17) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -1e+84) tmp = 1.0; elseif (x <= -3.5e-67) tmp = -1.0; elseif (x <= -1.65e-127) tmp = 1.0; elseif (x <= 2.35e-17) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -1e+84], 1.0, If[LessEqual[x, -3.5e-67], -1.0, If[LessEqual[x, -1.65e-127], 1.0, If[LessEqual[x, 2.35e-17], -1.0, 1.0]]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1 \cdot 10^{+84}:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq -3.5 \cdot 10^{-67}:\\
\;\;\;\;-1\\
\mathbf{elif}\;x \leq -1.65 \cdot 10^{-127}:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 2.35 \cdot 10^{-17}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -1.00000000000000006e84 or -3.5e-67 < x < -1.6499999999999999e-127 or 2.35e-17 < x Initial program 100.0%
Taylor expanded in x around inf 76.1%
if -1.00000000000000006e84 < x < -3.5e-67 or -1.6499999999999999e-127 < x < 2.35e-17Initial program 100.0%
Taylor expanded in x around 0 81.1%
Final simplification78.5%
(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 100.0%
Taylor expanded in x around 0 51.2%
Final simplification51.2%
(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 2023240
(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)))