
(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 (or (<= x -5.4e-8)
(and (not (<= x 5.5e-140)) (or (<= x 6e-24) (not (<= x 2.9e+69)))))
(+ 1.0 (* -2.0 (/ y x)))
-1.0))
double code(double x, double y) {
double tmp;
if ((x <= -5.4e-8) || (!(x <= 5.5e-140) && ((x <= 6e-24) || !(x <= 2.9e+69)))) {
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 <= (-5.4d-8)) .or. (.not. (x <= 5.5d-140)) .and. (x <= 6d-24) .or. (.not. (x <= 2.9d+69))) 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 <= -5.4e-8) || (!(x <= 5.5e-140) && ((x <= 6e-24) || !(x <= 2.9e+69)))) {
tmp = 1.0 + (-2.0 * (y / x));
} else {
tmp = -1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -5.4e-8) or (not (x <= 5.5e-140) and ((x <= 6e-24) or not (x <= 2.9e+69))): tmp = 1.0 + (-2.0 * (y / x)) else: tmp = -1.0 return tmp
function code(x, y) tmp = 0.0 if ((x <= -5.4e-8) || (!(x <= 5.5e-140) && ((x <= 6e-24) || !(x <= 2.9e+69)))) 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 <= -5.4e-8) || (~((x <= 5.5e-140)) && ((x <= 6e-24) || ~((x <= 2.9e+69))))) tmp = 1.0 + (-2.0 * (y / x)); else tmp = -1.0; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -5.4e-8], And[N[Not[LessEqual[x, 5.5e-140]], $MachinePrecision], Or[LessEqual[x, 6e-24], N[Not[LessEqual[x, 2.9e+69]], $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 -5.4 \cdot 10^{-8} \lor \neg \left(x \leq 5.5 \cdot 10^{-140}\right) \land \left(x \leq 6 \cdot 10^{-24} \lor \neg \left(x \leq 2.9 \cdot 10^{+69}\right)\right):\\
\;\;\;\;1 + -2 \cdot \frac{y}{x}\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if x < -5.40000000000000005e-8 or 5.50000000000000026e-140 < x < 5.99999999999999991e-24 or 2.8999999999999998e69 < x Initial program 100.0%
Taylor expanded in y around 0 84.1%
if -5.40000000000000005e-8 < x < 5.50000000000000026e-140 or 5.99999999999999991e-24 < x < 2.8999999999999998e69Initial program 100.0%
Taylor expanded in x around 0 77.1%
Final simplification80.6%
(FPCore (x y)
:precision binary64
(if (<= x -0.0001)
1.0
(if (<= x 5.5e-140)
-1.0
(if (<= x 3.3e-52) 1.0 (if (<= x 1.5e+71) -1.0 1.0)))))
double code(double x, double y) {
double tmp;
if (x <= -0.0001) {
tmp = 1.0;
} else if (x <= 5.5e-140) {
tmp = -1.0;
} else if (x <= 3.3e-52) {
tmp = 1.0;
} else if (x <= 1.5e+71) {
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 <= (-0.0001d0)) then
tmp = 1.0d0
else if (x <= 5.5d-140) then
tmp = -1.0d0
else if (x <= 3.3d-52) then
tmp = 1.0d0
else if (x <= 1.5d+71) 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 <= -0.0001) {
tmp = 1.0;
} else if (x <= 5.5e-140) {
tmp = -1.0;
} else if (x <= 3.3e-52) {
tmp = 1.0;
} else if (x <= 1.5e+71) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -0.0001: tmp = 1.0 elif x <= 5.5e-140: tmp = -1.0 elif x <= 3.3e-52: tmp = 1.0 elif x <= 1.5e+71: tmp = -1.0 else: tmp = 1.0 return tmp
function code(x, y) tmp = 0.0 if (x <= -0.0001) tmp = 1.0; elseif (x <= 5.5e-140) tmp = -1.0; elseif (x <= 3.3e-52) tmp = 1.0; elseif (x <= 1.5e+71) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -0.0001) tmp = 1.0; elseif (x <= 5.5e-140) tmp = -1.0; elseif (x <= 3.3e-52) tmp = 1.0; elseif (x <= 1.5e+71) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -0.0001], 1.0, If[LessEqual[x, 5.5e-140], -1.0, If[LessEqual[x, 3.3e-52], 1.0, If[LessEqual[x, 1.5e+71], -1.0, 1.0]]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -0.0001:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 5.5 \cdot 10^{-140}:\\
\;\;\;\;-1\\
\mathbf{elif}\;x \leq 3.3 \cdot 10^{-52}:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 1.5 \cdot 10^{+71}:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -1.00000000000000005e-4 or 5.50000000000000026e-140 < x < 3.29999999999999995e-52 or 1.50000000000000006e71 < x Initial program 100.0%
Taylor expanded in x around inf 84.0%
if -1.00000000000000005e-4 < x < 5.50000000000000026e-140 or 3.29999999999999995e-52 < x < 1.50000000000000006e71Initial program 100.0%
Taylor expanded in x around 0 76.3%
Final simplification80.1%
(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 46.8%
Final simplification46.8%
(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 2024040
(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)))