
(FPCore (x y) :precision binary64 (- (* x 2.0) y))
double code(double x, double y) {
return (x * 2.0) - y;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (x * 2.0d0) - y
end function
public static double code(double x, double y) {
return (x * 2.0) - y;
}
def code(x, y): return (x * 2.0) - y
function code(x, y) return Float64(Float64(x * 2.0) - y) end
function tmp = code(x, y) tmp = (x * 2.0) - y; end
code[x_, y_] := N[(N[(x * 2.0), $MachinePrecision] - y), $MachinePrecision]
\begin{array}{l}
\\
x \cdot 2 - y
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (- (* x 2.0) y))
double code(double x, double y) {
return (x * 2.0) - y;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (x * 2.0d0) - y
end function
public static double code(double x, double y) {
return (x * 2.0) - y;
}
def code(x, y): return (x * 2.0) - y
function code(x, y) return Float64(Float64(x * 2.0) - y) end
function tmp = code(x, y) tmp = (x * 2.0) - y; end
code[x_, y_] := N[(N[(x * 2.0), $MachinePrecision] - y), $MachinePrecision]
\begin{array}{l}
\\
x \cdot 2 - y
\end{array}
(FPCore (x y) :precision binary64 (- (* 2.0 x) y))
double code(double x, double y) {
return (2.0 * x) - y;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (2.0d0 * x) - y
end function
public static double code(double x, double y) {
return (2.0 * x) - y;
}
def code(x, y): return (2.0 * x) - y
function code(x, y) return Float64(Float64(2.0 * x) - y) end
function tmp = code(x, y) tmp = (2.0 * x) - y; end
code[x_, y_] := N[(N[(2.0 * x), $MachinePrecision] - y), $MachinePrecision]
\begin{array}{l}
\\
2 \cdot x - y
\end{array}
Initial program 100.0%
Final simplification100.0%
(FPCore (x y) :precision binary64 (if (<= y -2.8e-21) (- y) (if (<= y 4.8e-36) (* 2.0 x) (- y))))
double code(double x, double y) {
double tmp;
if (y <= -2.8e-21) {
tmp = -y;
} else if (y <= 4.8e-36) {
tmp = 2.0 * x;
} else {
tmp = -y;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (y <= (-2.8d-21)) then
tmp = -y
else if (y <= 4.8d-36) then
tmp = 2.0d0 * x
else
tmp = -y
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (y <= -2.8e-21) {
tmp = -y;
} else if (y <= 4.8e-36) {
tmp = 2.0 * x;
} else {
tmp = -y;
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -2.8e-21: tmp = -y elif y <= 4.8e-36: tmp = 2.0 * x else: tmp = -y return tmp
function code(x, y) tmp = 0.0 if (y <= -2.8e-21) tmp = Float64(-y); elseif (y <= 4.8e-36) tmp = Float64(2.0 * x); else tmp = Float64(-y); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (y <= -2.8e-21) tmp = -y; elseif (y <= 4.8e-36) tmp = 2.0 * x; else tmp = -y; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, -2.8e-21], (-y), If[LessEqual[y, 4.8e-36], N[(2.0 * x), $MachinePrecision], (-y)]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -2.8 \cdot 10^{-21}:\\
\;\;\;\;-y\\
\mathbf{elif}\;y \leq 4.8 \cdot 10^{-36}:\\
\;\;\;\;2 \cdot x\\
\mathbf{else}:\\
\;\;\;\;-y\\
\end{array}
\end{array}
if y < -2.80000000000000004e-21 or 4.8e-36 < y Initial program 100.0%
Taylor expanded in y around inf
mul-1-negN/A
lower-neg.f6475.1
Applied rewrites75.1%
if -2.80000000000000004e-21 < y < 4.8e-36Initial program 100.0%
Taylor expanded in y around 0
*-commutativeN/A
*-rgt-identityN/A
*-inversesN/A
associate-/l*N/A
*-commutativeN/A
associate-*l/N/A
associate-*r/N/A
associate-*r*N/A
*-commutativeN/A
associate-*r*N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
associate-*r/N/A
metadata-evalN/A
distribute-rgt-neg-inN/A
distribute-frac-negN/A
*-commutativeN/A
associate-/l*N/A
*-inversesN/A
metadata-evalN/A
metadata-eval81.1
Applied rewrites81.1%
(FPCore (x y) :precision binary64 (- y))
double code(double x, double y) {
return -y;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = -y
end function
public static double code(double x, double y) {
return -y;
}
def code(x, y): return -y
function code(x, y) return Float64(-y) end
function tmp = code(x, y) tmp = -y; end
code[x_, y_] := (-y)
\begin{array}{l}
\\
-y
\end{array}
Initial program 100.0%
Taylor expanded in y around inf
mul-1-negN/A
lower-neg.f6447.0
Applied rewrites47.0%
(FPCore (x y) :precision binary64 y)
double code(double x, double y) {
return y;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = y
end function
public static double code(double x, double y) {
return y;
}
def code(x, y): return y
function code(x, y) return y end
function tmp = code(x, y) tmp = y; end
code[x_, y_] := y
\begin{array}{l}
\\
y
\end{array}
Initial program 100.0%
Taylor expanded in y around inf
mul-1-negN/A
lower-neg.f6447.0
Applied rewrites47.0%
Applied rewrites2.5%
herbie shell --seed 2024264
(FPCore (x y)
:name "Data.Colour.RGBSpace.HSL:hsl from colour-2.3.3, C"
:precision binary64
(- (* x 2.0) y))