
(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 -5.4e-8) (- y) (if (<= y 4.3e-50) (* 2.0 x) (- y))))
double code(double x, double y) {
double tmp;
if (y <= -5.4e-8) {
tmp = -y;
} else if (y <= 4.3e-50) {
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 <= (-5.4d-8)) then
tmp = -y
else if (y <= 4.3d-50) 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 <= -5.4e-8) {
tmp = -y;
} else if (y <= 4.3e-50) {
tmp = 2.0 * x;
} else {
tmp = -y;
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -5.4e-8: tmp = -y elif y <= 4.3e-50: tmp = 2.0 * x else: tmp = -y return tmp
function code(x, y) tmp = 0.0 if (y <= -5.4e-8) tmp = Float64(-y); elseif (y <= 4.3e-50) tmp = Float64(2.0 * x); else tmp = Float64(-y); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (y <= -5.4e-8) tmp = -y; elseif (y <= 4.3e-50) tmp = 2.0 * x; else tmp = -y; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, -5.4e-8], (-y), If[LessEqual[y, 4.3e-50], N[(2.0 * x), $MachinePrecision], (-y)]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -5.4 \cdot 10^{-8}:\\
\;\;\;\;-y\\
\mathbf{elif}\;y \leq 4.3 \cdot 10^{-50}:\\
\;\;\;\;2 \cdot x\\
\mathbf{else}:\\
\;\;\;\;-y\\
\end{array}
\end{array}
if y < -5.40000000000000005e-8 or 4.29999999999999997e-50 < y Initial program 100.0%
Taylor expanded in x around 0
mul-1-negN/A
lower-neg.f6474.2
Applied rewrites74.2%
if -5.40000000000000005e-8 < y < 4.29999999999999997e-50Initial program 100.0%
Taylor expanded in x around 0
mul-1-negN/A
lower-neg.f6417.4
Applied rewrites17.4%
Taylor expanded in x around inf
lower-*.f6484.2
Applied rewrites84.2%
(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 x around 0
mul-1-negN/A
lower-neg.f6446.9
Applied rewrites46.9%
(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 x around 0
mul-1-negN/A
lower-neg.f6446.9
Applied rewrites46.9%
Applied rewrites2.2%
herbie shell --seed 2024327
(FPCore (x y)
:name "Data.Colour.RGBSpace.HSL:hsl from colour-2.3.3, C"
:precision binary64
(- (* x 2.0) y))