
(FPCore (x y) :precision binary64 (+ x (/ (- x y) 2.0)))
double code(double x, double y) {
return x + ((x - y) / 2.0);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x + ((x - y) / 2.0d0)
end function
public static double code(double x, double y) {
return x + ((x - y) / 2.0);
}
def code(x, y): return x + ((x - y) / 2.0)
function code(x, y) return Float64(x + Float64(Float64(x - y) / 2.0)) end
function tmp = code(x, y) tmp = x + ((x - y) / 2.0); end
code[x_, y_] := N[(x + N[(N[(x - y), $MachinePrecision] / 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \frac{x - y}{2}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (+ x (/ (- x y) 2.0)))
double code(double x, double y) {
return x + ((x - y) / 2.0);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x + ((x - y) / 2.0d0)
end function
public static double code(double x, double y) {
return x + ((x - y) / 2.0);
}
def code(x, y): return x + ((x - y) / 2.0)
function code(x, y) return Float64(x + Float64(Float64(x - y) / 2.0)) end
function tmp = code(x, y) tmp = x + ((x - y) / 2.0); end
code[x_, y_] := N[(x + N[(N[(x - y), $MachinePrecision] / 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \frac{x - y}{2}
\end{array}
(FPCore (x y) :precision binary64 (fma x 1.5 (* y -0.5)))
double code(double x, double y) {
return fma(x, 1.5, (y * -0.5));
}
function code(x, y) return fma(x, 1.5, Float64(y * -0.5)) end
code[x_, y_] := N[(x * 1.5 + N[(y * -0.5), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(x, 1.5, y \cdot -0.5\right)
\end{array}
Initial program 99.9%
div-sub99.9%
associate-+r-99.9%
remove-double-neg99.9%
distribute-frac-neg99.9%
sub-neg99.9%
neg-mul-199.9%
*-commutative99.9%
associate-/l*99.9%
*-rgt-identity99.9%
metadata-eval99.9%
distribute-lft-out--99.9%
fma-neg100.0%
metadata-eval100.0%
metadata-eval100.0%
metadata-eval100.0%
distribute-frac-neg100.0%
neg-mul-1100.0%
*-commutative100.0%
associate-/l*100.0%
metadata-eval100.0%
Simplified100.0%
(FPCore (x y)
:precision binary64
(if (or (<= x -1.15e+36)
(and (not (<= x -4.7e-99))
(or (<= x -1.15e-157) (not (<= x 3.7e-17)))))
(* x 1.5)
(* y -0.5)))
double code(double x, double y) {
double tmp;
if ((x <= -1.15e+36) || (!(x <= -4.7e-99) && ((x <= -1.15e-157) || !(x <= 3.7e-17)))) {
tmp = x * 1.5;
} else {
tmp = y * -0.5;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if ((x <= (-1.15d+36)) .or. (.not. (x <= (-4.7d-99))) .and. (x <= (-1.15d-157)) .or. (.not. (x <= 3.7d-17))) then
tmp = x * 1.5d0
else
tmp = y * (-0.5d0)
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((x <= -1.15e+36) || (!(x <= -4.7e-99) && ((x <= -1.15e-157) || !(x <= 3.7e-17)))) {
tmp = x * 1.5;
} else {
tmp = y * -0.5;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -1.15e+36) or (not (x <= -4.7e-99) and ((x <= -1.15e-157) or not (x <= 3.7e-17))): tmp = x * 1.5 else: tmp = y * -0.5 return tmp
function code(x, y) tmp = 0.0 if ((x <= -1.15e+36) || (!(x <= -4.7e-99) && ((x <= -1.15e-157) || !(x <= 3.7e-17)))) tmp = Float64(x * 1.5); else tmp = Float64(y * -0.5); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((x <= -1.15e+36) || (~((x <= -4.7e-99)) && ((x <= -1.15e-157) || ~((x <= 3.7e-17))))) tmp = x * 1.5; else tmp = y * -0.5; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -1.15e+36], And[N[Not[LessEqual[x, -4.7e-99]], $MachinePrecision], Or[LessEqual[x, -1.15e-157], N[Not[LessEqual[x, 3.7e-17]], $MachinePrecision]]]], N[(x * 1.5), $MachinePrecision], N[(y * -0.5), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.15 \cdot 10^{+36} \lor \neg \left(x \leq -4.7 \cdot 10^{-99}\right) \land \left(x \leq -1.15 \cdot 10^{-157} \lor \neg \left(x \leq 3.7 \cdot 10^{-17}\right)\right):\\
\;\;\;\;x \cdot 1.5\\
\mathbf{else}:\\
\;\;\;\;y \cdot -0.5\\
\end{array}
\end{array}
if x < -1.14999999999999998e36 or -4.69999999999999989e-99 < x < -1.14999999999999994e-157 or 3.6999999999999997e-17 < x Initial program 99.8%
Taylor expanded in x around inf 81.2%
if -1.14999999999999998e36 < x < -4.69999999999999989e-99 or -1.14999999999999994e-157 < x < 3.6999999999999997e-17Initial program 99.9%
Taylor expanded in x around 0 75.8%
Final simplification78.7%
(FPCore (x y) :precision binary64 (+ (* y -0.5) (* x 1.5)))
double code(double x, double y) {
return (y * -0.5) + (x * 1.5);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (y * (-0.5d0)) + (x * 1.5d0)
end function
public static double code(double x, double y) {
return (y * -0.5) + (x * 1.5);
}
def code(x, y): return (y * -0.5) + (x * 1.5)
function code(x, y) return Float64(Float64(y * -0.5) + Float64(x * 1.5)) end
function tmp = code(x, y) tmp = (y * -0.5) + (x * 1.5); end
code[x_, y_] := N[(N[(y * -0.5), $MachinePrecision] + N[(x * 1.5), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
y \cdot -0.5 + x \cdot 1.5
\end{array}
Initial program 99.9%
Taylor expanded in x around 0 99.9%
Final simplification99.9%
(FPCore (x y) :precision binary64 (+ x (/ (- x y) 2.0)))
double code(double x, double y) {
return x + ((x - y) / 2.0);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x + ((x - y) / 2.0d0)
end function
public static double code(double x, double y) {
return x + ((x - y) / 2.0);
}
def code(x, y): return x + ((x - y) / 2.0)
function code(x, y) return Float64(x + Float64(Float64(x - y) / 2.0)) end
function tmp = code(x, y) tmp = x + ((x - y) / 2.0); end
code[x_, y_] := N[(x + N[(N[(x - y), $MachinePrecision] / 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \frac{x - y}{2}
\end{array}
Initial program 99.9%
(FPCore (x y) :precision binary64 (* y -0.5))
double code(double x, double y) {
return y * -0.5;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = y * (-0.5d0)
end function
public static double code(double x, double y) {
return y * -0.5;
}
def code(x, y): return y * -0.5
function code(x, y) return Float64(y * -0.5) end
function tmp = code(x, y) tmp = y * -0.5; end
code[x_, y_] := N[(y * -0.5), $MachinePrecision]
\begin{array}{l}
\\
y \cdot -0.5
\end{array}
Initial program 99.9%
Taylor expanded in x around 0 45.2%
Final simplification45.2%
(FPCore (x y) :precision binary64 (- (* 1.5 x) (* 0.5 y)))
double code(double x, double y) {
return (1.5 * x) - (0.5 * y);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (1.5d0 * x) - (0.5d0 * y)
end function
public static double code(double x, double y) {
return (1.5 * x) - (0.5 * y);
}
def code(x, y): return (1.5 * x) - (0.5 * y)
function code(x, y) return Float64(Float64(1.5 * x) - Float64(0.5 * y)) end
function tmp = code(x, y) tmp = (1.5 * x) - (0.5 * y); end
code[x_, y_] := N[(N[(1.5 * x), $MachinePrecision] - N[(0.5 * y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
1.5 \cdot x - 0.5 \cdot y
\end{array}
herbie shell --seed 2024097
(FPCore (x y)
:name "Graphics.Rendering.Chart.Axis.Types:hBufferRect from Chart-1.5.3"
:precision binary64
:alt
(- (* 1.5 x) (* 0.5 y))
(+ x (/ (- x y) 2.0)))