
(FPCore (re im base) :precision binary64 (/ (+ (* (log (sqrt (+ (* re re) (* im im)))) (log base)) (* (atan2 im re) 0.0)) (+ (* (log base) (log base)) (* 0.0 0.0))))
double code(double re, double im, double base) {
return ((log(sqrt(((re * re) + (im * im)))) * log(base)) + (atan2(im, re) * 0.0)) / ((log(base) * log(base)) + (0.0 * 0.0));
}
real(8) function code(re, im, base)
real(8), intent (in) :: re
real(8), intent (in) :: im
real(8), intent (in) :: base
code = ((log(sqrt(((re * re) + (im * im)))) * log(base)) + (atan2(im, re) * 0.0d0)) / ((log(base) * log(base)) + (0.0d0 * 0.0d0))
end function
public static double code(double re, double im, double base) {
return ((Math.log(Math.sqrt(((re * re) + (im * im)))) * Math.log(base)) + (Math.atan2(im, re) * 0.0)) / ((Math.log(base) * Math.log(base)) + (0.0 * 0.0));
}
def code(re, im, base): return ((math.log(math.sqrt(((re * re) + (im * im)))) * math.log(base)) + (math.atan2(im, re) * 0.0)) / ((math.log(base) * math.log(base)) + (0.0 * 0.0))
function code(re, im, base) return Float64(Float64(Float64(log(sqrt(Float64(Float64(re * re) + Float64(im * im)))) * log(base)) + Float64(atan(im, re) * 0.0)) / Float64(Float64(log(base) * log(base)) + Float64(0.0 * 0.0))) end
function tmp = code(re, im, base) tmp = ((log(sqrt(((re * re) + (im * im)))) * log(base)) + (atan2(im, re) * 0.0)) / ((log(base) * log(base)) + (0.0 * 0.0)); end
code[re_, im_, base_] := N[(N[(N[(N[Log[N[Sqrt[N[(N[(re * re), $MachinePrecision] + N[(im * im), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision] * N[Log[base], $MachinePrecision]), $MachinePrecision] + N[(N[ArcTan[im / re], $MachinePrecision] * 0.0), $MachinePrecision]), $MachinePrecision] / N[(N[(N[Log[base], $MachinePrecision] * N[Log[base], $MachinePrecision]), $MachinePrecision] + N[(0.0 * 0.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right) \cdot \log base + \tan^{-1}_* \frac{im}{re} \cdot 0}{\log base \cdot \log base + 0 \cdot 0}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (re im base) :precision binary64 (/ (+ (* (log (sqrt (+ (* re re) (* im im)))) (log base)) (* (atan2 im re) 0.0)) (+ (* (log base) (log base)) (* 0.0 0.0))))
double code(double re, double im, double base) {
return ((log(sqrt(((re * re) + (im * im)))) * log(base)) + (atan2(im, re) * 0.0)) / ((log(base) * log(base)) + (0.0 * 0.0));
}
real(8) function code(re, im, base)
real(8), intent (in) :: re
real(8), intent (in) :: im
real(8), intent (in) :: base
code = ((log(sqrt(((re * re) + (im * im)))) * log(base)) + (atan2(im, re) * 0.0d0)) / ((log(base) * log(base)) + (0.0d0 * 0.0d0))
end function
public static double code(double re, double im, double base) {
return ((Math.log(Math.sqrt(((re * re) + (im * im)))) * Math.log(base)) + (Math.atan2(im, re) * 0.0)) / ((Math.log(base) * Math.log(base)) + (0.0 * 0.0));
}
def code(re, im, base): return ((math.log(math.sqrt(((re * re) + (im * im)))) * math.log(base)) + (math.atan2(im, re) * 0.0)) / ((math.log(base) * math.log(base)) + (0.0 * 0.0))
function code(re, im, base) return Float64(Float64(Float64(log(sqrt(Float64(Float64(re * re) + Float64(im * im)))) * log(base)) + Float64(atan(im, re) * 0.0)) / Float64(Float64(log(base) * log(base)) + Float64(0.0 * 0.0))) end
function tmp = code(re, im, base) tmp = ((log(sqrt(((re * re) + (im * im)))) * log(base)) + (atan2(im, re) * 0.0)) / ((log(base) * log(base)) + (0.0 * 0.0)); end
code[re_, im_, base_] := N[(N[(N[(N[Log[N[Sqrt[N[(N[(re * re), $MachinePrecision] + N[(im * im), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision] * N[Log[base], $MachinePrecision]), $MachinePrecision] + N[(N[ArcTan[im / re], $MachinePrecision] * 0.0), $MachinePrecision]), $MachinePrecision] / N[(N[(N[Log[base], $MachinePrecision] * N[Log[base], $MachinePrecision]), $MachinePrecision] + N[(0.0 * 0.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\log \left(\sqrt{re \cdot re + im \cdot im}\right) \cdot \log base + \tan^{-1}_* \frac{im}{re} \cdot 0}{\log base \cdot \log base + 0 \cdot 0}
\end{array}
(FPCore (re im base) :precision binary64 (/ (log (hypot re im)) (log base)))
double code(double re, double im, double base) {
return log(hypot(re, im)) / log(base);
}
public static double code(double re, double im, double base) {
return Math.log(Math.hypot(re, im)) / Math.log(base);
}
def code(re, im, base): return math.log(math.hypot(re, im)) / math.log(base)
function code(re, im, base) return Float64(log(hypot(re, im)) / log(base)) end
function tmp = code(re, im, base) tmp = log(hypot(re, im)) / log(base); end
code[re_, im_, base_] := N[(N[Log[N[Sqrt[re ^ 2 + im ^ 2], $MachinePrecision]], $MachinePrecision] / N[Log[base], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\log \left(\mathsf{hypot}\left(re, im\right)\right)}{\log base}
\end{array}
Initial program 52.5%
Taylor expanded in base around 0
lower-/.f64N/A
lower-log.f64N/A
+-commutativeN/A
unpow2N/A
unpow2N/A
lower-hypot.f64N/A
lower-log.f6499.4
Applied rewrites99.4%
(FPCore (re im base) :precision binary64 (/ (fma (/ (* 0.5 re) im) (/ re im) (log im)) (log base)))
double code(double re, double im, double base) {
return fma(((0.5 * re) / im), (re / im), log(im)) / log(base);
}
function code(re, im, base) return Float64(fma(Float64(Float64(0.5 * re) / im), Float64(re / im), log(im)) / log(base)) end
code[re_, im_, base_] := N[(N[(N[(N[(0.5 * re), $MachinePrecision] / im), $MachinePrecision] * N[(re / im), $MachinePrecision] + N[Log[im], $MachinePrecision]), $MachinePrecision] / N[Log[base], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(\frac{0.5 \cdot re}{im}, \frac{re}{im}, \log im\right)}{\log base}
\end{array}
Initial program 52.5%
lift-/.f64N/A
lift-+.f64N/A
lift-*.f64N/A
mul0-rgtN/A
metadata-evalN/A
sub-negN/A
lift-+.f64N/A
lift-*.f64N/A
metadata-evalN/A
+-rgt-identityN/A
lift-*.f64N/A
associate-/r*N/A
lower-/.f64N/A
Applied rewrites99.4%
Taylor expanded in re around 0
+-commutativeN/A
associate-*r/N/A
unpow2N/A
associate-*r*N/A
unpow2N/A
times-fracN/A
lower-fma.f64N/A
lower-/.f64N/A
lower-*.f64N/A
lower-/.f64N/A
lower-log.f6426.6
Applied rewrites26.6%
(FPCore (re im base) :precision binary64 (/ (log im) (log base)))
double code(double re, double im, double base) {
return log(im) / log(base);
}
real(8) function code(re, im, base)
real(8), intent (in) :: re
real(8), intent (in) :: im
real(8), intent (in) :: base
code = log(im) / log(base)
end function
public static double code(double re, double im, double base) {
return Math.log(im) / Math.log(base);
}
def code(re, im, base): return math.log(im) / math.log(base)
function code(re, im, base) return Float64(log(im) / log(base)) end
function tmp = code(re, im, base) tmp = log(im) / log(base); end
code[re_, im_, base_] := N[(N[Log[im], $MachinePrecision] / N[Log[base], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\log im}{\log base}
\end{array}
Initial program 52.5%
Taylor expanded in re around 0
lower-/.f64N/A
lower-log.f64N/A
lower-log.f6428.1
Applied rewrites28.1%
(FPCore (re im base) :precision binary64 (/ (* (* (/ 0.5 (* im im)) re) re) (log base)))
double code(double re, double im, double base) {
return (((0.5 / (im * im)) * re) * re) / log(base);
}
real(8) function code(re, im, base)
real(8), intent (in) :: re
real(8), intent (in) :: im
real(8), intent (in) :: base
code = (((0.5d0 / (im * im)) * re) * re) / log(base)
end function
public static double code(double re, double im, double base) {
return (((0.5 / (im * im)) * re) * re) / Math.log(base);
}
def code(re, im, base): return (((0.5 / (im * im)) * re) * re) / math.log(base)
function code(re, im, base) return Float64(Float64(Float64(Float64(0.5 / Float64(im * im)) * re) * re) / log(base)) end
function tmp = code(re, im, base) tmp = (((0.5 / (im * im)) * re) * re) / log(base); end
code[re_, im_, base_] := N[(N[(N[(N[(0.5 / N[(im * im), $MachinePrecision]), $MachinePrecision] * re), $MachinePrecision] * re), $MachinePrecision] / N[Log[base], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(\frac{0.5}{im \cdot im} \cdot re\right) \cdot re}{\log base}
\end{array}
Initial program 52.5%
lift-/.f64N/A
lift-+.f64N/A
lift-*.f64N/A
mul0-rgtN/A
metadata-evalN/A
sub-negN/A
lift-+.f64N/A
lift-*.f64N/A
metadata-evalN/A
+-rgt-identityN/A
lift-*.f64N/A
associate-/r*N/A
lower-/.f64N/A
Applied rewrites99.4%
Taylor expanded in re around 0
+-commutativeN/A
associate-*r/N/A
unpow2N/A
associate-*r*N/A
unpow2N/A
times-fracN/A
lower-fma.f64N/A
lower-/.f64N/A
lower-*.f64N/A
lower-/.f64N/A
lower-log.f6426.6
Applied rewrites26.6%
Taylor expanded in re around inf
Applied rewrites3.1%
herbie shell --seed 2024255
(FPCore (re im base)
:name "math.log/2 on complex, real part"
:precision binary64
(/ (+ (* (log (sqrt (+ (* re re) (* im im)))) (log base)) (* (atan2 im re) 0.0)) (+ (* (log base) (log base)) (* 0.0 0.0))))