
(FPCore (a b c d) :precision binary64 (/ (+ (* a c) (* b d)) (+ (* c c) (* d d))))
double code(double a, double b, double c, double d) {
return ((a * c) + (b * d)) / ((c * c) + (d * d));
}
real(8) function code(a, b, c, d)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
real(8), intent (in) :: d
code = ((a * c) + (b * d)) / ((c * c) + (d * d))
end function
public static double code(double a, double b, double c, double d) {
return ((a * c) + (b * d)) / ((c * c) + (d * d));
}
def code(a, b, c, d): return ((a * c) + (b * d)) / ((c * c) + (d * d))
function code(a, b, c, d) return Float64(Float64(Float64(a * c) + Float64(b * d)) / Float64(Float64(c * c) + Float64(d * d))) end
function tmp = code(a, b, c, d) tmp = ((a * c) + (b * d)) / ((c * c) + (d * d)); end
code[a_, b_, c_, d_] := N[(N[(N[(a * c), $MachinePrecision] + N[(b * d), $MachinePrecision]), $MachinePrecision] / N[(N[(c * c), $MachinePrecision] + N[(d * d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (a b c d) :precision binary64 (/ (+ (* a c) (* b d)) (+ (* c c) (* d d))))
double code(double a, double b, double c, double d) {
return ((a * c) + (b * d)) / ((c * c) + (d * d));
}
real(8) function code(a, b, c, d)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
real(8), intent (in) :: d
code = ((a * c) + (b * d)) / ((c * c) + (d * d))
end function
public static double code(double a, double b, double c, double d) {
return ((a * c) + (b * d)) / ((c * c) + (d * d));
}
def code(a, b, c, d): return ((a * c) + (b * d)) / ((c * c) + (d * d))
function code(a, b, c, d) return Float64(Float64(Float64(a * c) + Float64(b * d)) / Float64(Float64(c * c) + Float64(d * d))) end
function tmp = code(a, b, c, d) tmp = ((a * c) + (b * d)) / ((c * c) + (d * d)); end
code[a_, b_, c_, d_] := N[(N[(N[(a * c), $MachinePrecision] + N[(b * d), $MachinePrecision]), $MachinePrecision] / N[(N[(c * c), $MachinePrecision] + N[(d * d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d}
\end{array}
(FPCore (a b c d)
:precision binary64
(let* ((t_0 (/ (+ a (* b (/ d c))) c)))
(if (<= c -8e-71)
t_0
(if (<= c 1.6e-107)
(/ (+ b (/ (* a c) d)) d)
(if (<= c 9.5e+107) (/ (+ (* a c) (* b d)) (+ (* c c) (* d d))) t_0)))))
double code(double a, double b, double c, double d) {
double t_0 = (a + (b * (d / c))) / c;
double tmp;
if (c <= -8e-71) {
tmp = t_0;
} else if (c <= 1.6e-107) {
tmp = (b + ((a * c) / d)) / d;
} else if (c <= 9.5e+107) {
tmp = ((a * c) + (b * d)) / ((c * c) + (d * d));
} else {
tmp = t_0;
}
return tmp;
}
real(8) function code(a, b, c, d)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
real(8), intent (in) :: d
real(8) :: t_0
real(8) :: tmp
t_0 = (a + (b * (d / c))) / c
if (c <= (-8d-71)) then
tmp = t_0
else if (c <= 1.6d-107) then
tmp = (b + ((a * c) / d)) / d
else if (c <= 9.5d+107) then
tmp = ((a * c) + (b * d)) / ((c * c) + (d * d))
else
tmp = t_0
end if
code = tmp
end function
public static double code(double a, double b, double c, double d) {
double t_0 = (a + (b * (d / c))) / c;
double tmp;
if (c <= -8e-71) {
tmp = t_0;
} else if (c <= 1.6e-107) {
tmp = (b + ((a * c) / d)) / d;
} else if (c <= 9.5e+107) {
tmp = ((a * c) + (b * d)) / ((c * c) + (d * d));
} else {
tmp = t_0;
}
return tmp;
}
def code(a, b, c, d): t_0 = (a + (b * (d / c))) / c tmp = 0 if c <= -8e-71: tmp = t_0 elif c <= 1.6e-107: tmp = (b + ((a * c) / d)) / d elif c <= 9.5e+107: tmp = ((a * c) + (b * d)) / ((c * c) + (d * d)) else: tmp = t_0 return tmp
function code(a, b, c, d) t_0 = Float64(Float64(a + Float64(b * Float64(d / c))) / c) tmp = 0.0 if (c <= -8e-71) tmp = t_0; elseif (c <= 1.6e-107) tmp = Float64(Float64(b + Float64(Float64(a * c) / d)) / d); elseif (c <= 9.5e+107) tmp = Float64(Float64(Float64(a * c) + Float64(b * d)) / Float64(Float64(c * c) + Float64(d * d))); else tmp = t_0; end return tmp end
function tmp_2 = code(a, b, c, d) t_0 = (a + (b * (d / c))) / c; tmp = 0.0; if (c <= -8e-71) tmp = t_0; elseif (c <= 1.6e-107) tmp = (b + ((a * c) / d)) / d; elseif (c <= 9.5e+107) tmp = ((a * c) + (b * d)) / ((c * c) + (d * d)); else tmp = t_0; end tmp_2 = tmp; end
code[a_, b_, c_, d_] := Block[{t$95$0 = N[(N[(a + N[(b * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]}, If[LessEqual[c, -8e-71], t$95$0, If[LessEqual[c, 1.6e-107], N[(N[(b + N[(N[(a * c), $MachinePrecision] / d), $MachinePrecision]), $MachinePrecision] / d), $MachinePrecision], If[LessEqual[c, 9.5e+107], N[(N[(N[(a * c), $MachinePrecision] + N[(b * d), $MachinePrecision]), $MachinePrecision] / N[(N[(c * c), $MachinePrecision] + N[(d * d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], t$95$0]]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{a + b \cdot \frac{d}{c}}{c}\\
\mathbf{if}\;c \leq -8 \cdot 10^{-71}:\\
\;\;\;\;t\_0\\
\mathbf{elif}\;c \leq 1.6 \cdot 10^{-107}:\\
\;\;\;\;\frac{b + \frac{a \cdot c}{d}}{d}\\
\mathbf{elif}\;c \leq 9.5 \cdot 10^{+107}:\\
\;\;\;\;\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d}\\
\mathbf{else}:\\
\;\;\;\;t\_0\\
\end{array}
\end{array}
if c < -7.9999999999999993e-71 or 9.50000000000000019e107 < c Initial program 48.2%
Taylor expanded in c around inf 79.3%
associate-/l*85.7%
Simplified85.7%
if -7.9999999999999993e-71 < c < 1.60000000000000006e-107Initial program 74.7%
Taylor expanded in d around inf 93.8%
if 1.60000000000000006e-107 < c < 9.50000000000000019e107Initial program 76.6%
(FPCore (a b c d) :precision binary64 (if (<= (/ (+ (* a c) (* b d)) (+ (* c c) (* d d))) 4e+247) (* (/ 1.0 (hypot c d)) (/ (fma a c (* b d)) (hypot c d))) (/ (+ a (* b (/ d c))) c)))
double code(double a, double b, double c, double d) {
double tmp;
if ((((a * c) + (b * d)) / ((c * c) + (d * d))) <= 4e+247) {
tmp = (1.0 / hypot(c, d)) * (fma(a, c, (b * d)) / hypot(c, d));
} else {
tmp = (a + (b * (d / c))) / c;
}
return tmp;
}
function code(a, b, c, d) tmp = 0.0 if (Float64(Float64(Float64(a * c) + Float64(b * d)) / Float64(Float64(c * c) + Float64(d * d))) <= 4e+247) tmp = Float64(Float64(1.0 / hypot(c, d)) * Float64(fma(a, c, Float64(b * d)) / hypot(c, d))); else tmp = Float64(Float64(a + Float64(b * Float64(d / c))) / c); end return tmp end
code[a_, b_, c_, d_] := If[LessEqual[N[(N[(N[(a * c), $MachinePrecision] + N[(b * d), $MachinePrecision]), $MachinePrecision] / N[(N[(c * c), $MachinePrecision] + N[(d * d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 4e+247], N[(N[(1.0 / N[Sqrt[c ^ 2 + d ^ 2], $MachinePrecision]), $MachinePrecision] * N[(N[(a * c + N[(b * d), $MachinePrecision]), $MachinePrecision] / N[Sqrt[c ^ 2 + d ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(a + N[(b * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \leq 4 \cdot 10^{+247}:\\
\;\;\;\;\frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\mathsf{hypot}\left(c, d\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\
\end{array}
\end{array}
if (/.f64 (+.f64 (*.f64 a c) (*.f64 b d)) (+.f64 (*.f64 c c) (*.f64 d d))) < 3.99999999999999981e247Initial program 80.4%
*-un-lft-identity80.4%
add-sqr-sqrt80.4%
times-frac80.5%
hypot-define80.5%
fma-define80.5%
hypot-define96.1%
Applied egg-rr96.1%
if 3.99999999999999981e247 < (/.f64 (+.f64 (*.f64 a c) (*.f64 b d)) (+.f64 (*.f64 c c) (*.f64 d d))) Initial program 11.2%
Taylor expanded in c around inf 49.5%
associate-/l*61.3%
Simplified61.3%
(FPCore (a b c d) :precision binary64 (if (or (<= c -8e-71) (not (<= c 1.02e+107))) (/ (+ a (* b (/ d c))) c) (/ (+ b (* a (/ c d))) d)))
double code(double a, double b, double c, double d) {
double tmp;
if ((c <= -8e-71) || !(c <= 1.02e+107)) {
tmp = (a + (b * (d / c))) / c;
} else {
tmp = (b + (a * (c / d))) / d;
}
return tmp;
}
real(8) function code(a, b, c, d)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
real(8), intent (in) :: d
real(8) :: tmp
if ((c <= (-8d-71)) .or. (.not. (c <= 1.02d+107))) then
tmp = (a + (b * (d / c))) / c
else
tmp = (b + (a * (c / d))) / d
end if
code = tmp
end function
public static double code(double a, double b, double c, double d) {
double tmp;
if ((c <= -8e-71) || !(c <= 1.02e+107)) {
tmp = (a + (b * (d / c))) / c;
} else {
tmp = (b + (a * (c / d))) / d;
}
return tmp;
}
def code(a, b, c, d): tmp = 0 if (c <= -8e-71) or not (c <= 1.02e+107): tmp = (a + (b * (d / c))) / c else: tmp = (b + (a * (c / d))) / d return tmp
function code(a, b, c, d) tmp = 0.0 if ((c <= -8e-71) || !(c <= 1.02e+107)) tmp = Float64(Float64(a + Float64(b * Float64(d / c))) / c); else tmp = Float64(Float64(b + Float64(a * Float64(c / d))) / d); end return tmp end
function tmp_2 = code(a, b, c, d) tmp = 0.0; if ((c <= -8e-71) || ~((c <= 1.02e+107))) tmp = (a + (b * (d / c))) / c; else tmp = (b + (a * (c / d))) / d; end tmp_2 = tmp; end
code[a_, b_, c_, d_] := If[Or[LessEqual[c, -8e-71], N[Not[LessEqual[c, 1.02e+107]], $MachinePrecision]], N[(N[(a + N[(b * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision], N[(N[(b + N[(a * N[(c / d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / d), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;c \leq -8 \cdot 10^{-71} \lor \neg \left(c \leq 1.02 \cdot 10^{+107}\right):\\
\;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\
\mathbf{else}:\\
\;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d}\\
\end{array}
\end{array}
if c < -7.9999999999999993e-71 or 1.01999999999999994e107 < c Initial program 48.2%
Taylor expanded in c around inf 79.3%
associate-/l*85.7%
Simplified85.7%
if -7.9999999999999993e-71 < c < 1.01999999999999994e107Initial program 75.3%
Taylor expanded in d around inf 81.3%
associate-/l*81.4%
Simplified81.4%
Final simplification83.5%
(FPCore (a b c d) :precision binary64 (if (or (<= d -6.8e-16) (not (<= d 3.1e+72))) (/ b d) (/ (+ a (* b (/ d c))) c)))
double code(double a, double b, double c, double d) {
double tmp;
if ((d <= -6.8e-16) || !(d <= 3.1e+72)) {
tmp = b / d;
} else {
tmp = (a + (b * (d / c))) / c;
}
return tmp;
}
real(8) function code(a, b, c, d)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
real(8), intent (in) :: d
real(8) :: tmp
if ((d <= (-6.8d-16)) .or. (.not. (d <= 3.1d+72))) then
tmp = b / d
else
tmp = (a + (b * (d / c))) / c
end if
code = tmp
end function
public static double code(double a, double b, double c, double d) {
double tmp;
if ((d <= -6.8e-16) || !(d <= 3.1e+72)) {
tmp = b / d;
} else {
tmp = (a + (b * (d / c))) / c;
}
return tmp;
}
def code(a, b, c, d): tmp = 0 if (d <= -6.8e-16) or not (d <= 3.1e+72): tmp = b / d else: tmp = (a + (b * (d / c))) / c return tmp
function code(a, b, c, d) tmp = 0.0 if ((d <= -6.8e-16) || !(d <= 3.1e+72)) tmp = Float64(b / d); else tmp = Float64(Float64(a + Float64(b * Float64(d / c))) / c); end return tmp end
function tmp_2 = code(a, b, c, d) tmp = 0.0; if ((d <= -6.8e-16) || ~((d <= 3.1e+72))) tmp = b / d; else tmp = (a + (b * (d / c))) / c; end tmp_2 = tmp; end
code[a_, b_, c_, d_] := If[Or[LessEqual[d, -6.8e-16], N[Not[LessEqual[d, 3.1e+72]], $MachinePrecision]], N[(b / d), $MachinePrecision], N[(N[(a + N[(b * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;d \leq -6.8 \cdot 10^{-16} \lor \neg \left(d \leq 3.1 \cdot 10^{+72}\right):\\
\;\;\;\;\frac{b}{d}\\
\mathbf{else}:\\
\;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\
\end{array}
\end{array}
if d < -6.8e-16 or 3.09999999999999988e72 < d Initial program 52.6%
Taylor expanded in c around 0 70.5%
if -6.8e-16 < d < 3.09999999999999988e72Initial program 70.5%
Taylor expanded in c around inf 83.3%
associate-/l*84.7%
Simplified84.7%
Final simplification78.2%
(FPCore (a b c d) :precision binary64 (if (or (<= c -3.8e-64) (not (<= c 3.5e+95))) (/ a c) (/ b d)))
double code(double a, double b, double c, double d) {
double tmp;
if ((c <= -3.8e-64) || !(c <= 3.5e+95)) {
tmp = a / c;
} else {
tmp = b / d;
}
return tmp;
}
real(8) function code(a, b, c, d)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
real(8), intent (in) :: d
real(8) :: tmp
if ((c <= (-3.8d-64)) .or. (.not. (c <= 3.5d+95))) then
tmp = a / c
else
tmp = b / d
end if
code = tmp
end function
public static double code(double a, double b, double c, double d) {
double tmp;
if ((c <= -3.8e-64) || !(c <= 3.5e+95)) {
tmp = a / c;
} else {
tmp = b / d;
}
return tmp;
}
def code(a, b, c, d): tmp = 0 if (c <= -3.8e-64) or not (c <= 3.5e+95): tmp = a / c else: tmp = b / d return tmp
function code(a, b, c, d) tmp = 0.0 if ((c <= -3.8e-64) || !(c <= 3.5e+95)) tmp = Float64(a / c); else tmp = Float64(b / d); end return tmp end
function tmp_2 = code(a, b, c, d) tmp = 0.0; if ((c <= -3.8e-64) || ~((c <= 3.5e+95))) tmp = a / c; else tmp = b / d; end tmp_2 = tmp; end
code[a_, b_, c_, d_] := If[Or[LessEqual[c, -3.8e-64], N[Not[LessEqual[c, 3.5e+95]], $MachinePrecision]], N[(a / c), $MachinePrecision], N[(b / d), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;c \leq -3.8 \cdot 10^{-64} \lor \neg \left(c \leq 3.5 \cdot 10^{+95}\right):\\
\;\;\;\;\frac{a}{c}\\
\mathbf{else}:\\
\;\;\;\;\frac{b}{d}\\
\end{array}
\end{array}
if c < -3.8000000000000002e-64 or 3.5e95 < c Initial program 47.4%
Taylor expanded in c around inf 68.4%
if -3.8000000000000002e-64 < c < 3.5e95Initial program 76.0%
Taylor expanded in c around 0 68.8%
Final simplification68.6%
(FPCore (a b c d) :precision binary64 (/ a c))
double code(double a, double b, double c, double d) {
return a / c;
}
real(8) function code(a, b, c, d)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
real(8), intent (in) :: d
code = a / c
end function
public static double code(double a, double b, double c, double d) {
return a / c;
}
def code(a, b, c, d): return a / c
function code(a, b, c, d) return Float64(a / c) end
function tmp = code(a, b, c, d) tmp = a / c; end
code[a_, b_, c_, d_] := N[(a / c), $MachinePrecision]
\begin{array}{l}
\\
\frac{a}{c}
\end{array}
Initial program 62.3%
Taylor expanded in c around inf 41.5%
(FPCore (a b c d) :precision binary64 (if (< (fabs d) (fabs c)) (/ (+ a (* b (/ d c))) (+ c (* d (/ d c)))) (/ (+ b (* a (/ c d))) (+ d (* c (/ c d))))))
double code(double a, double b, double c, double d) {
double tmp;
if (fabs(d) < fabs(c)) {
tmp = (a + (b * (d / c))) / (c + (d * (d / c)));
} else {
tmp = (b + (a * (c / d))) / (d + (c * (c / d)));
}
return tmp;
}
real(8) function code(a, b, c, d)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8), intent (in) :: c
real(8), intent (in) :: d
real(8) :: tmp
if (abs(d) < abs(c)) then
tmp = (a + (b * (d / c))) / (c + (d * (d / c)))
else
tmp = (b + (a * (c / d))) / (d + (c * (c / d)))
end if
code = tmp
end function
public static double code(double a, double b, double c, double d) {
double tmp;
if (Math.abs(d) < Math.abs(c)) {
tmp = (a + (b * (d / c))) / (c + (d * (d / c)));
} else {
tmp = (b + (a * (c / d))) / (d + (c * (c / d)));
}
return tmp;
}
def code(a, b, c, d): tmp = 0 if math.fabs(d) < math.fabs(c): tmp = (a + (b * (d / c))) / (c + (d * (d / c))) else: tmp = (b + (a * (c / d))) / (d + (c * (c / d))) return tmp
function code(a, b, c, d) tmp = 0.0 if (abs(d) < abs(c)) tmp = Float64(Float64(a + Float64(b * Float64(d / c))) / Float64(c + Float64(d * Float64(d / c)))); else tmp = Float64(Float64(b + Float64(a * Float64(c / d))) / Float64(d + Float64(c * Float64(c / d)))); end return tmp end
function tmp_2 = code(a, b, c, d) tmp = 0.0; if (abs(d) < abs(c)) tmp = (a + (b * (d / c))) / (c + (d * (d / c))); else tmp = (b + (a * (c / d))) / (d + (c * (c / d))); end tmp_2 = tmp; end
code[a_, b_, c_, d_] := If[Less[N[Abs[d], $MachinePrecision], N[Abs[c], $MachinePrecision]], N[(N[(a + N[(b * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(c + N[(d * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(b + N[(a * N[(c / d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(d + N[(c * N[(c / d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\left|d\right| < \left|c\right|:\\
\;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c + d \cdot \frac{d}{c}}\\
\mathbf{else}:\\
\;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d + c \cdot \frac{c}{d}}\\
\end{array}
\end{array}
herbie shell --seed 2024113
(FPCore (a b c d)
:name "Complex division, real part"
:precision binary64
:alt
(! :herbie-platform default (if (< (fabs d) (fabs c)) (/ (+ a (* b (/ d c))) (+ c (* d (/ d c)))) (/ (+ b (* a (/ c d))) (+ d (* c (/ c d))))))
(/ (+ (* a c) (* b d)) (+ (* c c) (* d d))))