
(FPCore (x) :precision binary64 (* (* x x) (- 3.0 (* x 2.0))))
double code(double x) {
return (x * x) * (3.0 - (x * 2.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (x * x) * (3.0d0 - (x * 2.0d0))
end function
public static double code(double x) {
return (x * x) * (3.0 - (x * 2.0));
}
def code(x): return (x * x) * (3.0 - (x * 2.0))
function code(x) return Float64(Float64(x * x) * Float64(3.0 - Float64(x * 2.0))) end
function tmp = code(x) tmp = (x * x) * (3.0 - (x * 2.0)); end
code[x_] := N[(N[(x * x), $MachinePrecision] * N[(3.0 - N[(x * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(x \cdot x\right) \cdot \left(3 - x \cdot 2\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (* (* x x) (- 3.0 (* x 2.0))))
double code(double x) {
return (x * x) * (3.0 - (x * 2.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (x * x) * (3.0d0 - (x * 2.0d0))
end function
public static double code(double x) {
return (x * x) * (3.0 - (x * 2.0));
}
def code(x): return (x * x) * (3.0 - (x * 2.0))
function code(x) return Float64(Float64(x * x) * Float64(3.0 - Float64(x * 2.0))) end
function tmp = code(x) tmp = (x * x) * (3.0 - (x * 2.0)); end
code[x_] := N[(N[(x * x), $MachinePrecision] * N[(3.0 - N[(x * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(x \cdot x\right) \cdot \left(3 - x \cdot 2\right)
\end{array}
(FPCore (x) :precision binary64 (fma (* x 3.0) x (* (pow x 3.0) -2.0)))
double code(double x) {
return fma((x * 3.0), x, (pow(x, 3.0) * -2.0));
}
function code(x) return fma(Float64(x * 3.0), x, Float64((x ^ 3.0) * -2.0)) end
code[x_] := N[(N[(x * 3.0), $MachinePrecision] * x + N[(N[Power[x, 3.0], $MachinePrecision] * -2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(x \cdot 3, x, {x}^{3} \cdot -2\right)
\end{array}
Initial program 99.7%
associate-*l*99.8%
Simplified99.8%
*-commutative99.8%
cancel-sign-sub-inv99.8%
metadata-eval99.8%
*-commutative99.8%
distribute-lft-in99.8%
fma-define99.8%
add-sqr-sqrt41.7%
sqrt-unprod73.9%
swap-sqr73.9%
metadata-eval73.9%
metadata-eval73.9%
swap-sqr73.9%
sqrt-unprod32.2%
add-sqr-sqrt51.0%
Applied egg-rr51.0%
fma-undefine51.0%
distribute-lft-in51.0%
*-commutative51.0%
*-commutative51.0%
add-sqr-sqrt32.2%
sqrt-unprod73.9%
swap-sqr73.9%
metadata-eval73.9%
metadata-eval73.9%
swap-sqr73.9%
sqrt-unprod41.7%
add-sqr-sqrt91.6%
*-commutative91.6%
associate-*r*91.6%
associate-*r*91.6%
cube-mult91.7%
*-commutative91.7%
fma-define99.9%
*-commutative99.9%
Applied egg-rr99.9%
(FPCore (x) :precision binary64 (if (or (<= x -1.5) (not (<= x 1.5))) (* x (* x (* x -2.0))) (* x (* x 3.0))))
double code(double x) {
double tmp;
if ((x <= -1.5) || !(x <= 1.5)) {
tmp = x * (x * (x * -2.0));
} else {
tmp = x * (x * 3.0);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if ((x <= (-1.5d0)) .or. (.not. (x <= 1.5d0))) then
tmp = x * (x * (x * (-2.0d0)))
else
tmp = x * (x * 3.0d0)
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if ((x <= -1.5) || !(x <= 1.5)) {
tmp = x * (x * (x * -2.0));
} else {
tmp = x * (x * 3.0);
}
return tmp;
}
def code(x): tmp = 0 if (x <= -1.5) or not (x <= 1.5): tmp = x * (x * (x * -2.0)) else: tmp = x * (x * 3.0) return tmp
function code(x) tmp = 0.0 if ((x <= -1.5) || !(x <= 1.5)) tmp = Float64(x * Float64(x * Float64(x * -2.0))); else tmp = Float64(x * Float64(x * 3.0)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if ((x <= -1.5) || ~((x <= 1.5))) tmp = x * (x * (x * -2.0)); else tmp = x * (x * 3.0); end tmp_2 = tmp; end
code[x_] := If[Or[LessEqual[x, -1.5], N[Not[LessEqual[x, 1.5]], $MachinePrecision]], N[(x * N[(x * N[(x * -2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x * N[(x * 3.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.5 \lor \neg \left(x \leq 1.5\right):\\
\;\;\;\;x \cdot \left(x \cdot \left(x \cdot -2\right)\right)\\
\mathbf{else}:\\
\;\;\;\;x \cdot \left(x \cdot 3\right)\\
\end{array}
\end{array}
if x < -1.5 or 1.5 < x Initial program 99.8%
associate-*l*99.8%
Simplified99.8%
Taylor expanded in x around inf 98.5%
*-commutative98.5%
Simplified98.5%
if -1.5 < x < 1.5Initial program 99.7%
associate-*l*99.8%
Simplified99.8%
Taylor expanded in x around 0 95.9%
*-commutative95.9%
Simplified95.9%
Final simplification97.1%
(FPCore (x) :precision binary64 (* x (* x (- 3.0 (* x 2.0)))))
double code(double x) {
return x * (x * (3.0 - (x * 2.0)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = x * (x * (3.0d0 - (x * 2.0d0)))
end function
public static double code(double x) {
return x * (x * (3.0 - (x * 2.0)));
}
def code(x): return x * (x * (3.0 - (x * 2.0)))
function code(x) return Float64(x * Float64(x * Float64(3.0 - Float64(x * 2.0)))) end
function tmp = code(x) tmp = x * (x * (3.0 - (x * 2.0))); end
code[x_] := N[(x * N[(x * N[(3.0 - N[(x * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \left(x \cdot \left(3 - x \cdot 2\right)\right)
\end{array}
Initial program 99.7%
associate-*l*99.8%
Simplified99.8%
(FPCore (x) :precision binary64 (* x (* x 3.0)))
double code(double x) {
return x * (x * 3.0);
}
real(8) function code(x)
real(8), intent (in) :: x
code = x * (x * 3.0d0)
end function
public static double code(double x) {
return x * (x * 3.0);
}
def code(x): return x * (x * 3.0)
function code(x) return Float64(x * Float64(x * 3.0)) end
function tmp = code(x) tmp = x * (x * 3.0); end
code[x_] := N[(x * N[(x * 3.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \left(x \cdot 3\right)
\end{array}
Initial program 99.7%
associate-*l*99.8%
Simplified99.8%
Taylor expanded in x around 0 65.9%
*-commutative65.9%
Simplified65.9%
(FPCore (x) :precision binary64 (* x (* x (- 3.0 (* x 2.0)))))
double code(double x) {
return x * (x * (3.0 - (x * 2.0)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = x * (x * (3.0d0 - (x * 2.0d0)))
end function
public static double code(double x) {
return x * (x * (3.0 - (x * 2.0)));
}
def code(x): return x * (x * (3.0 - (x * 2.0)))
function code(x) return Float64(x * Float64(x * Float64(3.0 - Float64(x * 2.0)))) end
function tmp = code(x) tmp = x * (x * (3.0 - (x * 2.0))); end
code[x_] := N[(x * N[(x * N[(3.0 - N[(x * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \left(x \cdot \left(3 - x \cdot 2\right)\right)
\end{array}
herbie shell --seed 2024181
(FPCore (x)
:name "Data.Spline.Key:interpolateKeys from smoothie-0.4.0.2"
:precision binary64
:alt
(! :herbie-platform default (* x (* x (- 3 (* x 2)))))
(* (* x x) (- 3.0 (* x 2.0))))