
(FPCore (x) :precision binary64 (sqrt (* 2.0 (* x x))))
double code(double x) {
return sqrt((2.0 * (x * x)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = sqrt((2.0d0 * (x * x)))
end function
public static double code(double x) {
return Math.sqrt((2.0 * (x * x)));
}
def code(x): return math.sqrt((2.0 * (x * x)))
function code(x) return sqrt(Float64(2.0 * Float64(x * x))) end
function tmp = code(x) tmp = sqrt((2.0 * (x * x))); end
code[x_] := N[Sqrt[N[(2.0 * N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{2 \cdot \left(x \cdot x\right)}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (sqrt (* 2.0 (* x x))))
double code(double x) {
return sqrt((2.0 * (x * x)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = sqrt((2.0d0 * (x * x)))
end function
public static double code(double x) {
return Math.sqrt((2.0 * (x * x)));
}
def code(x): return math.sqrt((2.0 * (x * x)))
function code(x) return sqrt(Float64(2.0 * Float64(x * x))) end
function tmp = code(x) tmp = sqrt((2.0 * (x * x))); end
code[x_] := N[Sqrt[N[(2.0 * N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{2 \cdot \left(x \cdot x\right)}
\end{array}
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 (* (sqrt x_m) (sqrt (* 2.0 x_m))))
x_m = fabs(x);
double code(double x_m) {
return sqrt(x_m) * sqrt((2.0 * x_m));
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
code = sqrt(x_m) * sqrt((2.0d0 * x_m))
end function
x_m = Math.abs(x);
public static double code(double x_m) {
return Math.sqrt(x_m) * Math.sqrt((2.0 * x_m));
}
x_m = math.fabs(x) def code(x_m): return math.sqrt(x_m) * math.sqrt((2.0 * x_m))
x_m = abs(x) function code(x_m) return Float64(sqrt(x_m) * sqrt(Float64(2.0 * x_m))) end
x_m = abs(x); function tmp = code(x_m) tmp = sqrt(x_m) * sqrt((2.0 * x_m)); end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := N[(N[Sqrt[x$95$m], $MachinePrecision] * N[Sqrt[N[(2.0 * x$95$m), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
\sqrt{x\_m} \cdot \sqrt{2 \cdot x\_m}
\end{array}
Initial program 52.6%
lift-sqrt.f64N/A
pow1/2N/A
lift-*.f64N/A
lift-*.f64N/A
associate-*r*N/A
unpow-prod-downN/A
lower-*.f64N/A
pow1/2N/A
lower-sqrt.f64N/A
*-commutativeN/A
lower-*.f64N/A
pow1/2N/A
lower-sqrt.f6450.5
Applied rewrites50.5%
Final simplification50.5%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 (* (sqrt 2.0) x_m))
x_m = fabs(x);
double code(double x_m) {
return sqrt(2.0) * x_m;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
code = sqrt(2.0d0) * x_m
end function
x_m = Math.abs(x);
public static double code(double x_m) {
return Math.sqrt(2.0) * x_m;
}
x_m = math.fabs(x) def code(x_m): return math.sqrt(2.0) * x_m
x_m = abs(x) function code(x_m) return Float64(sqrt(2.0) * x_m) end
x_m = abs(x); function tmp = code(x_m) tmp = sqrt(2.0) * x_m; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := N[(N[Sqrt[2.0], $MachinePrecision] * x$95$m), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
\sqrt{2} \cdot x\_m
\end{array}
Initial program 52.6%
lift-sqrt.f64N/A
lift-*.f64N/A
sqrt-prodN/A
pow1/2N/A
lift-*.f64N/A
sqrt-prodN/A
rem-square-sqrtN/A
lower-*.f64N/A
pow1/2N/A
lower-sqrt.f6451.5
Applied rewrites51.5%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 x_m)
x_m = fabs(x);
double code(double x_m) {
return x_m;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
code = x_m
end function
x_m = Math.abs(x);
public static double code(double x_m) {
return x_m;
}
x_m = math.fabs(x) def code(x_m): return x_m
x_m = abs(x) function code(x_m) return x_m end
x_m = abs(x); function tmp = code(x_m) tmp = x_m; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := x$95$m
\begin{array}{l}
x_m = \left|x\right|
\\
x\_m
\end{array}
Initial program 52.6%
lift-sqrt.f64N/A
lift-*.f64N/A
sqrt-prodN/A
pow1/2N/A
lift-*.f64N/A
sqrt-prodN/A
rem-square-sqrtN/A
lower-*.f64N/A
pow1/2N/A
lower-sqrt.f6451.5
Applied rewrites51.5%
lift-sqrt.f64N/A
pow1/2N/A
metadata-evalN/A
pow-sqrN/A
pow-prod-downN/A
metadata-evalN/A
metadata-evalN/A
pow-powN/A
lift-pow.f64N/A
lower-pow.f6451.4
lift-pow.f64N/A
sqr-powN/A
pow-prod-downN/A
sqr-powN/A
pow-prod-downN/A
lower-pow.f64N/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
metadata-eval51.4
Applied rewrites51.4%
Applied rewrites11.4%
lift-*.f64N/A
*-rgt-identity11.4
Applied rewrites11.4%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 1.0)
x_m = fabs(x);
double code(double x_m) {
return 1.0;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
code = 1.0d0
end function
x_m = Math.abs(x);
public static double code(double x_m) {
return 1.0;
}
x_m = math.fabs(x) def code(x_m): return 1.0
x_m = abs(x) function code(x_m) return 1.0 end
x_m = abs(x); function tmp = code(x_m) tmp = 1.0; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := 1.0
\begin{array}{l}
x_m = \left|x\right|
\\
1
\end{array}
Initial program 52.6%
lift-sqrt.f64N/A
lift-*.f64N/A
sqrt-prodN/A
pow1/2N/A
lift-*.f64N/A
sqrt-prodN/A
rem-square-sqrtN/A
lower-*.f64N/A
pow1/2N/A
lower-sqrt.f6451.5
Applied rewrites51.5%
lift-sqrt.f64N/A
pow1/2N/A
metadata-evalN/A
pow-sqrN/A
pow-prod-downN/A
metadata-evalN/A
metadata-evalN/A
pow-powN/A
lift-pow.f64N/A
lower-pow.f6451.4
lift-pow.f64N/A
sqr-powN/A
pow-prod-downN/A
sqr-powN/A
pow-prod-downN/A
lower-pow.f64N/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
metadata-eval51.4
Applied rewrites51.4%
Applied rewrites11.4%
lift-*.f64N/A
*-rgt-identity11.4
rem-square-sqrtN/A
lift-sqrt.f64N/A
lift-sqrt.f64N/A
pow2N/A
metadata-evalN/A
metadata-evalN/A
sqrt-pow2N/A
lift-sqrt.f64N/A
pow-to-expN/A
metadata-evalN/A
metadata-evalN/A
distribute-rgt-outN/A
distribute-lft-inN/A
flip-+N/A
+-inversesN/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
+-inversesN/A
metadata-evalN/A
flip--N/A
metadata-evalN/A
Applied rewrites5.4%
herbie shell --seed 2024248
(FPCore (x)
:name "sqrt C (should all be same)"
:precision binary64
(sqrt (* 2.0 (* x x))))