
(FPCore (re im) :precision binary64 (* 0.5 (sqrt (* 2.0 (- (sqrt (+ (* re re) (* im im))) re)))))
double code(double re, double im) {
return 0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) - re)));
}
real(8) function code(re, im)
real(8), intent (in) :: re
real(8), intent (in) :: im
code = 0.5d0 * sqrt((2.0d0 * (sqrt(((re * re) + (im * im))) - re)))
end function
public static double code(double re, double im) {
return 0.5 * Math.sqrt((2.0 * (Math.sqrt(((re * re) + (im * im))) - re)));
}
def code(re, im): return 0.5 * math.sqrt((2.0 * (math.sqrt(((re * re) + (im * im))) - re)))
function code(re, im) return Float64(0.5 * sqrt(Float64(2.0 * Float64(sqrt(Float64(Float64(re * re) + Float64(im * im))) - re)))) end
function tmp = code(re, im) tmp = 0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) - re))); end
code[re_, im_] := N[(0.5 * N[Sqrt[N[(2.0 * N[(N[Sqrt[N[(N[(re * re), $MachinePrecision] + N[(im * im), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 8 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (re im) :precision binary64 (* 0.5 (sqrt (* 2.0 (- (sqrt (+ (* re re) (* im im))) re)))))
double code(double re, double im) {
return 0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) - re)));
}
real(8) function code(re, im)
real(8), intent (in) :: re
real(8), intent (in) :: im
code = 0.5d0 * sqrt((2.0d0 * (sqrt(((re * re) + (im * im))) - re)))
end function
public static double code(double re, double im) {
return 0.5 * Math.sqrt((2.0 * (Math.sqrt(((re * re) + (im * im))) - re)));
}
def code(re, im): return 0.5 * math.sqrt((2.0 * (math.sqrt(((re * re) + (im * im))) - re)))
function code(re, im) return Float64(0.5 * sqrt(Float64(2.0 * Float64(sqrt(Float64(Float64(re * re) + Float64(im * im))) - re)))) end
function tmp = code(re, im) tmp = 0.5 * sqrt((2.0 * (sqrt(((re * re) + (im * im))) - re))); end
code[re_, im_] := N[(0.5 * N[Sqrt[N[(2.0 * N[(N[Sqrt[N[(N[(re * re), $MachinePrecision] + N[(im * im), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 \cdot \sqrt{2 \cdot \left(\sqrt{re \cdot re + im \cdot im} - re\right)}
\end{array}
(FPCore (re im) :precision binary64 (if (<= re 5.7e-70) (* (sqrt (* (- (hypot re im) re) 2.0)) 0.5) (* (sqrt (/ 1.0 re)) (* im 0.5))))
double code(double re, double im) {
double tmp;
if (re <= 5.7e-70) {
tmp = sqrt(((hypot(re, im) - re) * 2.0)) * 0.5;
} else {
tmp = sqrt((1.0 / re)) * (im * 0.5);
}
return tmp;
}
public static double code(double re, double im) {
double tmp;
if (re <= 5.7e-70) {
tmp = Math.sqrt(((Math.hypot(re, im) - re) * 2.0)) * 0.5;
} else {
tmp = Math.sqrt((1.0 / re)) * (im * 0.5);
}
return tmp;
}
def code(re, im): tmp = 0 if re <= 5.7e-70: tmp = math.sqrt(((math.hypot(re, im) - re) * 2.0)) * 0.5 else: tmp = math.sqrt((1.0 / re)) * (im * 0.5) return tmp
function code(re, im) tmp = 0.0 if (re <= 5.7e-70) tmp = Float64(sqrt(Float64(Float64(hypot(re, im) - re) * 2.0)) * 0.5); else tmp = Float64(sqrt(Float64(1.0 / re)) * Float64(im * 0.5)); end return tmp end
function tmp_2 = code(re, im) tmp = 0.0; if (re <= 5.7e-70) tmp = sqrt(((hypot(re, im) - re) * 2.0)) * 0.5; else tmp = sqrt((1.0 / re)) * (im * 0.5); end tmp_2 = tmp; end
code[re_, im_] := If[LessEqual[re, 5.7e-70], N[(N[Sqrt[N[(N[(N[Sqrt[re ^ 2 + im ^ 2], $MachinePrecision] - re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[Sqrt[N[(1.0 / re), $MachinePrecision]], $MachinePrecision] * N[(im * 0.5), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;re \leq 5.7 \cdot 10^{-70}:\\
\;\;\;\;\sqrt{\left(\mathsf{hypot}\left(re, im\right) - re\right) \cdot 2} \cdot 0.5\\
\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{1}{re}} \cdot \left(im \cdot 0.5\right)\\
\end{array}
\end{array}
if re < 5.70000000000000028e-70Initial program 58.7%
lift-sqrt.f64N/A
lift-+.f64N/A
lift-*.f64N/A
lift-*.f64N/A
lower-hypot.f6498.9
Applied rewrites98.9%
if 5.70000000000000028e-70 < re Initial program 12.0%
Taylor expanded in re around inf
associate-*r*N/A
lower-*.f64N/A
associate-*r*N/A
associate-*r*N/A
lower-*.f64N/A
lower-*.f64N/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
lower-/.f6479.7
Applied rewrites79.7%
Applied rewrites80.4%
Final simplification93.0%
(FPCore (re im)
:precision binary64
(if (<= re -2.7e+145)
(* (sqrt (* -4.0 re)) 0.5)
(if (<= re -3e-151)
(* (sqrt (* (- (sqrt (+ (* im im) (* re re))) re) 2.0)) 0.5)
(if (<= re 5.7e-70)
(* (sqrt (* (- im re) 2.0)) 0.5)
(* (sqrt (/ 1.0 re)) (* im 0.5))))))
double code(double re, double im) {
double tmp;
if (re <= -2.7e+145) {
tmp = sqrt((-4.0 * re)) * 0.5;
} else if (re <= -3e-151) {
tmp = sqrt(((sqrt(((im * im) + (re * re))) - re) * 2.0)) * 0.5;
} else if (re <= 5.7e-70) {
tmp = sqrt(((im - re) * 2.0)) * 0.5;
} else {
tmp = sqrt((1.0 / re)) * (im * 0.5);
}
return tmp;
}
real(8) function code(re, im)
real(8), intent (in) :: re
real(8), intent (in) :: im
real(8) :: tmp
if (re <= (-2.7d+145)) then
tmp = sqrt(((-4.0d0) * re)) * 0.5d0
else if (re <= (-3d-151)) then
tmp = sqrt(((sqrt(((im * im) + (re * re))) - re) * 2.0d0)) * 0.5d0
else if (re <= 5.7d-70) then
tmp = sqrt(((im - re) * 2.0d0)) * 0.5d0
else
tmp = sqrt((1.0d0 / re)) * (im * 0.5d0)
end if
code = tmp
end function
public static double code(double re, double im) {
double tmp;
if (re <= -2.7e+145) {
tmp = Math.sqrt((-4.0 * re)) * 0.5;
} else if (re <= -3e-151) {
tmp = Math.sqrt(((Math.sqrt(((im * im) + (re * re))) - re) * 2.0)) * 0.5;
} else if (re <= 5.7e-70) {
tmp = Math.sqrt(((im - re) * 2.0)) * 0.5;
} else {
tmp = Math.sqrt((1.0 / re)) * (im * 0.5);
}
return tmp;
}
def code(re, im): tmp = 0 if re <= -2.7e+145: tmp = math.sqrt((-4.0 * re)) * 0.5 elif re <= -3e-151: tmp = math.sqrt(((math.sqrt(((im * im) + (re * re))) - re) * 2.0)) * 0.5 elif re <= 5.7e-70: tmp = math.sqrt(((im - re) * 2.0)) * 0.5 else: tmp = math.sqrt((1.0 / re)) * (im * 0.5) return tmp
function code(re, im) tmp = 0.0 if (re <= -2.7e+145) tmp = Float64(sqrt(Float64(-4.0 * re)) * 0.5); elseif (re <= -3e-151) tmp = Float64(sqrt(Float64(Float64(sqrt(Float64(Float64(im * im) + Float64(re * re))) - re) * 2.0)) * 0.5); elseif (re <= 5.7e-70) tmp = Float64(sqrt(Float64(Float64(im - re) * 2.0)) * 0.5); else tmp = Float64(sqrt(Float64(1.0 / re)) * Float64(im * 0.5)); end return tmp end
function tmp_2 = code(re, im) tmp = 0.0; if (re <= -2.7e+145) tmp = sqrt((-4.0 * re)) * 0.5; elseif (re <= -3e-151) tmp = sqrt(((sqrt(((im * im) + (re * re))) - re) * 2.0)) * 0.5; elseif (re <= 5.7e-70) tmp = sqrt(((im - re) * 2.0)) * 0.5; else tmp = sqrt((1.0 / re)) * (im * 0.5); end tmp_2 = tmp; end
code[re_, im_] := If[LessEqual[re, -2.7e+145], N[(N[Sqrt[N[(-4.0 * re), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], If[LessEqual[re, -3e-151], N[(N[Sqrt[N[(N[(N[Sqrt[N[(N[(im * im), $MachinePrecision] + N[(re * re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], If[LessEqual[re, 5.7e-70], N[(N[Sqrt[N[(N[(im - re), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision], N[(N[Sqrt[N[(1.0 / re), $MachinePrecision]], $MachinePrecision] * N[(im * 0.5), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;re \leq -2.7 \cdot 10^{+145}:\\
\;\;\;\;\sqrt{-4 \cdot re} \cdot 0.5\\
\mathbf{elif}\;re \leq -3 \cdot 10^{-151}:\\
\;\;\;\;\sqrt{\left(\sqrt{im \cdot im + re \cdot re} - re\right) \cdot 2} \cdot 0.5\\
\mathbf{elif}\;re \leq 5.7 \cdot 10^{-70}:\\
\;\;\;\;\sqrt{\left(im - re\right) \cdot 2} \cdot 0.5\\
\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{1}{re}} \cdot \left(im \cdot 0.5\right)\\
\end{array}
\end{array}
if re < -2.70000000000000022e145Initial program 7.3%
Taylor expanded in re around -inf
lower-*.f6486.7
Applied rewrites86.7%
if -2.70000000000000022e145 < re < -3e-151Initial program 76.3%
if -3e-151 < re < 5.70000000000000028e-70Initial program 53.2%
Taylor expanded in re around 0
mul-1-negN/A
unsub-negN/A
lower--.f6484.2
Applied rewrites84.2%
if 5.70000000000000028e-70 < re Initial program 15.7%
Taylor expanded in re around inf
associate-*r*N/A
lower-*.f64N/A
associate-*r*N/A
associate-*r*N/A
lower-*.f64N/A
lower-*.f64N/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
lower-/.f6470.2
Applied rewrites70.2%
Applied rewrites70.7%
Final simplification78.5%
herbie shell --seed 2024234
(FPCore (re im)
:name "math.sqrt on complex, imaginary part, im greater than 0 branch"
:precision binary64
:pre (> im 0.0)
(* 0.5 (sqrt (* 2.0 (- (sqrt (+ (* re re) (* im im))) re)))))