
(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 6 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 1.95e-63) (* 0.5 (sqrt (* 2.0 (- (hypot re im) re)))) (* 0.5 (* im (pow re -0.5)))))
double code(double re, double im) {
double tmp;
if (re <= 1.95e-63) {
tmp = 0.5 * sqrt((2.0 * (hypot(re, im) - re)));
} else {
tmp = 0.5 * (im * pow(re, -0.5));
}
return tmp;
}
public static double code(double re, double im) {
double tmp;
if (re <= 1.95e-63) {
tmp = 0.5 * Math.sqrt((2.0 * (Math.hypot(re, im) - re)));
} else {
tmp = 0.5 * (im * Math.pow(re, -0.5));
}
return tmp;
}
def code(re, im): tmp = 0 if re <= 1.95e-63: tmp = 0.5 * math.sqrt((2.0 * (math.hypot(re, im) - re))) else: tmp = 0.5 * (im * math.pow(re, -0.5)) return tmp
function code(re, im) tmp = 0.0 if (re <= 1.95e-63) tmp = Float64(0.5 * sqrt(Float64(2.0 * Float64(hypot(re, im) - re)))); else tmp = Float64(0.5 * Float64(im * (re ^ -0.5))); end return tmp end
function tmp_2 = code(re, im) tmp = 0.0; if (re <= 1.95e-63) tmp = 0.5 * sqrt((2.0 * (hypot(re, im) - re))); else tmp = 0.5 * (im * (re ^ -0.5)); end tmp_2 = tmp; end
code[re_, im_] := If[LessEqual[re, 1.95e-63], N[(0.5 * N[Sqrt[N[(2.0 * N[(N[Sqrt[re ^ 2 + im ^ 2], $MachinePrecision] - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[(im * N[Power[re, -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;re \leq 1.95 \cdot 10^{-63}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(\mathsf{hypot}\left(re, im\right) - re\right)}\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\
\end{array}
\end{array}
(FPCore (re im)
:precision binary64
(if (<= re -4.9e+26)
(* 0.5 (sqrt (* re -4.0)))
(if (<= re 3.8e-64)
(* 0.5 (sqrt (* 2.0 (- im re))))
(* 0.5 (* im (pow re -0.5))))))
double code(double re, double im) {
double tmp;
if (re <= -4.9e+26) {
tmp = 0.5 * sqrt((re * -4.0));
} else if (re <= 3.8e-64) {
tmp = 0.5 * sqrt((2.0 * (im - re)));
} else {
tmp = 0.5 * (im * pow(re, -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 <= (-4.9d+26)) then
tmp = 0.5d0 * sqrt((re * (-4.0d0)))
else if (re <= 3.8d-64) then
tmp = 0.5d0 * sqrt((2.0d0 * (im - re)))
else
tmp = 0.5d0 * (im * (re ** (-0.5d0)))
end if
code = tmp
end function
public static double code(double re, double im) {
double tmp;
if (re <= -4.9e+26) {
tmp = 0.5 * Math.sqrt((re * -4.0));
} else if (re <= 3.8e-64) {
tmp = 0.5 * Math.sqrt((2.0 * (im - re)));
} else {
tmp = 0.5 * (im * Math.pow(re, -0.5));
}
return tmp;
}
def code(re, im): tmp = 0 if re <= -4.9e+26: tmp = 0.5 * math.sqrt((re * -4.0)) elif re <= 3.8e-64: tmp = 0.5 * math.sqrt((2.0 * (im - re))) else: tmp = 0.5 * (im * math.pow(re, -0.5)) return tmp
function code(re, im) tmp = 0.0 if (re <= -4.9e+26) tmp = Float64(0.5 * sqrt(Float64(re * -4.0))); elseif (re <= 3.8e-64) tmp = Float64(0.5 * sqrt(Float64(2.0 * Float64(im - re)))); else tmp = Float64(0.5 * Float64(im * (re ^ -0.5))); end return tmp end
function tmp_2 = code(re, im) tmp = 0.0; if (re <= -4.9e+26) tmp = 0.5 * sqrt((re * -4.0)); elseif (re <= 3.8e-64) tmp = 0.5 * sqrt((2.0 * (im - re))); else tmp = 0.5 * (im * (re ^ -0.5)); end tmp_2 = tmp; end
code[re_, im_] := If[LessEqual[re, -4.9e+26], N[(0.5 * N[Sqrt[N[(re * -4.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 3.8e-64], N[(0.5 * N[Sqrt[N[(2.0 * N[(im - re), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[(im * N[Power[re, -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;re \leq -4.9 \cdot 10^{+26}:\\
\;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\
\mathbf{elif}\;re \leq 3.8 \cdot 10^{-64}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot \left(im - re\right)}\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\
\end{array}
\end{array}
(FPCore (re im)
:precision binary64
(if (<= re -3.5e+26)
(* 0.5 (sqrt (* re -4.0)))
(if (<= re 3.5e-63)
(* 0.5 (sqrt (* 2.0 im)))
(* 0.5 (* im (pow re -0.5))))))
double code(double re, double im) {
double tmp;
if (re <= -3.5e+26) {
tmp = 0.5 * sqrt((re * -4.0));
} else if (re <= 3.5e-63) {
tmp = 0.5 * sqrt((2.0 * im));
} else {
tmp = 0.5 * (im * pow(re, -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 <= (-3.5d+26)) then
tmp = 0.5d0 * sqrt((re * (-4.0d0)))
else if (re <= 3.5d-63) then
tmp = 0.5d0 * sqrt((2.0d0 * im))
else
tmp = 0.5d0 * (im * (re ** (-0.5d0)))
end if
code = tmp
end function
public static double code(double re, double im) {
double tmp;
if (re <= -3.5e+26) {
tmp = 0.5 * Math.sqrt((re * -4.0));
} else if (re <= 3.5e-63) {
tmp = 0.5 * Math.sqrt((2.0 * im));
} else {
tmp = 0.5 * (im * Math.pow(re, -0.5));
}
return tmp;
}
def code(re, im): tmp = 0 if re <= -3.5e+26: tmp = 0.5 * math.sqrt((re * -4.0)) elif re <= 3.5e-63: tmp = 0.5 * math.sqrt((2.0 * im)) else: tmp = 0.5 * (im * math.pow(re, -0.5)) return tmp
function code(re, im) tmp = 0.0 if (re <= -3.5e+26) tmp = Float64(0.5 * sqrt(Float64(re * -4.0))); elseif (re <= 3.5e-63) tmp = Float64(0.5 * sqrt(Float64(2.0 * im))); else tmp = Float64(0.5 * Float64(im * (re ^ -0.5))); end return tmp end
function tmp_2 = code(re, im) tmp = 0.0; if (re <= -3.5e+26) tmp = 0.5 * sqrt((re * -4.0)); elseif (re <= 3.5e-63) tmp = 0.5 * sqrt((2.0 * im)); else tmp = 0.5 * (im * (re ^ -0.5)); end tmp_2 = tmp; end
code[re_, im_] := If[LessEqual[re, -3.5e+26], N[(0.5 * N[Sqrt[N[(re * -4.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 3.5e-63], N[(0.5 * N[Sqrt[N[(2.0 * im), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[(im * N[Power[re, -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;re \leq -3.5 \cdot 10^{+26}:\\
\;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\
\mathbf{elif}\;re \leq 3.5 \cdot 10^{-63}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot im}\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot \left(im \cdot {re}^{-0.5}\right)\\
\end{array}
\end{array}
(FPCore (re im) :precision binary64 (if (<= re -2.85e+26) (* 0.5 (sqrt (* re -4.0))) (if (<= re 1.35e-63) (* 0.5 (sqrt (* 2.0 im))) (* 0.5 (/ im (sqrt re))))))
double code(double re, double im) {
double tmp;
if (re <= -2.85e+26) {
tmp = 0.5 * sqrt((re * -4.0));
} else if (re <= 1.35e-63) {
tmp = 0.5 * sqrt((2.0 * im));
} else {
tmp = 0.5 * (im / sqrt(re));
}
return tmp;
}
real(8) function code(re, im)
real(8), intent (in) :: re
real(8), intent (in) :: im
real(8) :: tmp
if (re <= (-2.85d+26)) then
tmp = 0.5d0 * sqrt((re * (-4.0d0)))
else if (re <= 1.35d-63) then
tmp = 0.5d0 * sqrt((2.0d0 * im))
else
tmp = 0.5d0 * (im / sqrt(re))
end if
code = tmp
end function
public static double code(double re, double im) {
double tmp;
if (re <= -2.85e+26) {
tmp = 0.5 * Math.sqrt((re * -4.0));
} else if (re <= 1.35e-63) {
tmp = 0.5 * Math.sqrt((2.0 * im));
} else {
tmp = 0.5 * (im / Math.sqrt(re));
}
return tmp;
}
def code(re, im): tmp = 0 if re <= -2.85e+26: tmp = 0.5 * math.sqrt((re * -4.0)) elif re <= 1.35e-63: tmp = 0.5 * math.sqrt((2.0 * im)) else: tmp = 0.5 * (im / math.sqrt(re)) return tmp
function code(re, im) tmp = 0.0 if (re <= -2.85e+26) tmp = Float64(0.5 * sqrt(Float64(re * -4.0))); elseif (re <= 1.35e-63) tmp = Float64(0.5 * sqrt(Float64(2.0 * im))); else tmp = Float64(0.5 * Float64(im / sqrt(re))); end return tmp end
function tmp_2 = code(re, im) tmp = 0.0; if (re <= -2.85e+26) tmp = 0.5 * sqrt((re * -4.0)); elseif (re <= 1.35e-63) tmp = 0.5 * sqrt((2.0 * im)); else tmp = 0.5 * (im / sqrt(re)); end tmp_2 = tmp; end
code[re_, im_] := If[LessEqual[re, -2.85e+26], N[(0.5 * N[Sqrt[N[(re * -4.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[re, 1.35e-63], N[(0.5 * N[Sqrt[N[(2.0 * im), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[(im / N[Sqrt[re], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;re \leq -2.85 \cdot 10^{+26}:\\
\;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\
\mathbf{elif}\;re \leq 1.35 \cdot 10^{-63}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot im}\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot \frac{im}{\sqrt{re}}\\
\end{array}
\end{array}
(FPCore (re im) :precision binary64 (if (<= re -4.1e+26) (* 0.5 (sqrt (* re -4.0))) (* 0.5 (sqrt (* 2.0 im)))))
double code(double re, double im) {
double tmp;
if (re <= -4.1e+26) {
tmp = 0.5 * sqrt((re * -4.0));
} else {
tmp = 0.5 * sqrt((2.0 * im));
}
return tmp;
}
real(8) function code(re, im)
real(8), intent (in) :: re
real(8), intent (in) :: im
real(8) :: tmp
if (re <= (-4.1d+26)) then
tmp = 0.5d0 * sqrt((re * (-4.0d0)))
else
tmp = 0.5d0 * sqrt((2.0d0 * im))
end if
code = tmp
end function
public static double code(double re, double im) {
double tmp;
if (re <= -4.1e+26) {
tmp = 0.5 * Math.sqrt((re * -4.0));
} else {
tmp = 0.5 * Math.sqrt((2.0 * im));
}
return tmp;
}
def code(re, im): tmp = 0 if re <= -4.1e+26: tmp = 0.5 * math.sqrt((re * -4.0)) else: tmp = 0.5 * math.sqrt((2.0 * im)) return tmp
function code(re, im) tmp = 0.0 if (re <= -4.1e+26) tmp = Float64(0.5 * sqrt(Float64(re * -4.0))); else tmp = Float64(0.5 * sqrt(Float64(2.0 * im))); end return tmp end
function tmp_2 = code(re, im) tmp = 0.0; if (re <= -4.1e+26) tmp = 0.5 * sqrt((re * -4.0)); else tmp = 0.5 * sqrt((2.0 * im)); end tmp_2 = tmp; end
code[re_, im_] := If[LessEqual[re, -4.1e+26], N[(0.5 * N[Sqrt[N[(re * -4.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(0.5 * N[Sqrt[N[(2.0 * im), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;re \leq -4.1 \cdot 10^{+26}:\\
\;\;\;\;0.5 \cdot \sqrt{re \cdot -4}\\
\mathbf{else}:\\
\;\;\;\;0.5 \cdot \sqrt{2 \cdot im}\\
\end{array}
\end{array}
(FPCore (re im) :precision binary64 (* 0.5 (sqrt (* 2.0 im))))
double code(double re, double im) {
return 0.5 * sqrt((2.0 * im));
}
real(8) function code(re, im)
real(8), intent (in) :: re
real(8), intent (in) :: im
code = 0.5d0 * sqrt((2.0d0 * im))
end function
public static double code(double re, double im) {
return 0.5 * Math.sqrt((2.0 * im));
}
def code(re, im): return 0.5 * math.sqrt((2.0 * im))
function code(re, im) return Float64(0.5 * sqrt(Float64(2.0 * im))) end
function tmp = code(re, im) tmp = 0.5 * sqrt((2.0 * im)); end
code[re_, im_] := N[(0.5 * N[Sqrt[N[(2.0 * im), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 \cdot \sqrt{2 \cdot im}
\end{array}
herbie shell --seed 2023343
(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)))))