
(FPCore (x y z) :precision binary64 (- (* x (log (/ x y))) z))
double code(double x, double y, double z) {
return (x * log((x / y))) - z;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = (x * log((x / y))) - z
end function
public static double code(double x, double y, double z) {
return (x * Math.log((x / y))) - z;
}
def code(x, y, z): return (x * math.log((x / y))) - z
function code(x, y, z) return Float64(Float64(x * log(Float64(x / y))) - z) end
function tmp = code(x, y, z) tmp = (x * log((x / y))) - z; end
code[x_, y_, z_] := N[(N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \log \left(\frac{x}{y}\right) - z
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y z) :precision binary64 (- (* x (log (/ x y))) z))
double code(double x, double y, double z) {
return (x * log((x / y))) - z;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = (x * log((x / y))) - z
end function
public static double code(double x, double y, double z) {
return (x * Math.log((x / y))) - z;
}
def code(x, y, z): return (x * math.log((x / y))) - z
function code(x, y, z) return Float64(Float64(x * log(Float64(x / y))) - z) end
function tmp = code(x, y, z) tmp = (x * log((x / y))) - z; end
code[x_, y_, z_] := N[(N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \log \left(\frac{x}{y}\right) - z
\end{array}
(FPCore (x y z) :precision binary64 (- (* x (* (log (/ (cbrt x) (cbrt y))) 3.0)) z))
double code(double x, double y, double z) {
return (x * (log((cbrt(x) / cbrt(y))) * 3.0)) - z;
}
public static double code(double x, double y, double z) {
return (x * (Math.log((Math.cbrt(x) / Math.cbrt(y))) * 3.0)) - z;
}
function code(x, y, z) return Float64(Float64(x * Float64(log(Float64(cbrt(x) / cbrt(y))) * 3.0)) - z) end
code[x_, y_, z_] := N[(N[(x * N[(N[Log[N[(N[Power[x, 1/3], $MachinePrecision] / N[Power[y, 1/3], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * 3.0), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \left(\log \left(\frac{\sqrt[3]{x}}{\sqrt[3]{y}}\right) \cdot 3\right) - z
\end{array}
Initial program 86.4%
add-cube-cbrt86.4%
log-prod86.3%
pow286.3%
Applied egg-rr86.3%
log-pow86.3%
distribute-lft1-in86.3%
metadata-eval86.3%
*-commutative86.3%
Simplified86.3%
cbrt-div99.7%
div-inv99.7%
Applied egg-rr99.7%
associate-*r/99.7%
*-rgt-identity99.7%
Simplified99.7%
Final simplification99.7%
(FPCore (x y z) :precision binary64 (let* ((t_0 (* x (log (/ x y))))) (if (<= t_0 (- INFINITY)) (- (* x (log (* x y))) z) (- t_0 z))))
double code(double x, double y, double z) {
double t_0 = x * log((x / y));
double tmp;
if (t_0 <= -((double) INFINITY)) {
tmp = (x * log((x * y))) - z;
} else {
tmp = t_0 - z;
}
return tmp;
}
public static double code(double x, double y, double z) {
double t_0 = x * Math.log((x / y));
double tmp;
if (t_0 <= -Double.POSITIVE_INFINITY) {
tmp = (x * Math.log((x * y))) - z;
} else {
tmp = t_0 - z;
}
return tmp;
}
def code(x, y, z): t_0 = x * math.log((x / y)) tmp = 0 if t_0 <= -math.inf: tmp = (x * math.log((x * y))) - z else: tmp = t_0 - z return tmp
function code(x, y, z) t_0 = Float64(x * log(Float64(x / y))) tmp = 0.0 if (t_0 <= Float64(-Inf)) tmp = Float64(Float64(x * log(Float64(x * y))) - z); else tmp = Float64(t_0 - z); end return tmp end
function tmp_2 = code(x, y, z) t_0 = x * log((x / y)); tmp = 0.0; if (t_0 <= -Inf) tmp = (x * log((x * y))) - z; else tmp = t_0 - z; end tmp_2 = tmp; end
code[x_, y_, z_] := Block[{t$95$0 = N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, (-Infinity)], N[(N[(x * N[Log[N[(x * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], N[(t$95$0 - z), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := x \cdot \log \left(\frac{x}{y}\right)\\
\mathbf{if}\;t_0 \leq -\infty:\\
\;\;\;\;x \cdot \log \left(x \cdot y\right) - z\\
\mathbf{else}:\\
\;\;\;\;t_0 - z\\
\end{array}
\end{array}
if (*.f64 x (log.f64 (/.f64 x y))) < -inf.0Initial program 4.0%
add-cube-cbrt4.0%
log-prod4.0%
pow24.0%
Applied egg-rr4.0%
log-pow4.0%
distribute-lft1-in4.0%
metadata-eval4.0%
*-commutative4.0%
Simplified4.0%
Applied egg-rr70.6%
distribute-rgt-out70.4%
sub-neg70.4%
*-commutative70.4%
sub-neg70.4%
add-sqr-sqrt0.0%
sqrt-unprod58.4%
sqr-neg58.4%
sqrt-unprod58.4%
add-sqr-sqrt58.4%
sum-log62.7%
Applied egg-rr62.7%
if -inf.0 < (*.f64 x (log.f64 (/.f64 x y))) Initial program 92.2%
Final simplification90.3%
(FPCore (x y z) :precision binary64 (if (<= y -2e-310) (- (* x (- (log (- x)) (log (- y)))) z) (- (* x (- (log x) (log y))) z)))
double code(double x, double y, double z) {
double tmp;
if (y <= -2e-310) {
tmp = (x * (log(-x) - log(-y))) - z;
} else {
tmp = (x * (log(x) - log(y))) - z;
}
return tmp;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8) :: tmp
if (y <= (-2d-310)) then
tmp = (x * (log(-x) - log(-y))) - z
else
tmp = (x * (log(x) - log(y))) - z
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (y <= -2e-310) {
tmp = (x * (Math.log(-x) - Math.log(-y))) - z;
} else {
tmp = (x * (Math.log(x) - Math.log(y))) - z;
}
return tmp;
}
def code(x, y, z): tmp = 0 if y <= -2e-310: tmp = (x * (math.log(-x) - math.log(-y))) - z else: tmp = (x * (math.log(x) - math.log(y))) - z return tmp
function code(x, y, z) tmp = 0.0 if (y <= -2e-310) tmp = Float64(Float64(x * Float64(log(Float64(-x)) - log(Float64(-y)))) - z); else tmp = Float64(Float64(x * Float64(log(x) - log(y))) - z); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (y <= -2e-310) tmp = (x * (log(-x) - log(-y))) - z; else tmp = (x * (log(x) - log(y))) - z; end tmp_2 = tmp; end
code[x_, y_, z_] := If[LessEqual[y, -2e-310], N[(N[(x * N[(N[Log[(-x)], $MachinePrecision] - N[Log[(-y)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], N[(N[(x * N[(N[Log[x], $MachinePrecision] - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -2 \cdot 10^{-310}:\\
\;\;\;\;x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right) - z\\
\mathbf{else}:\\
\;\;\;\;x \cdot \left(\log x - \log y\right) - z\\
\end{array}
\end{array}
if y < -1.999999999999994e-310Initial program 90.9%
frac-2neg90.9%
log-div99.6%
Applied egg-rr99.6%
if -1.999999999999994e-310 < y Initial program 83.0%
log-div99.5%
Applied egg-rr99.5%
Final simplification99.5%
(FPCore (x y z) :precision binary64 (if (<= y -2e-310) (- (* x (- (log (- x)) (log (- y)))) z) (- (- (* x (log x)) (* x (log y))) z)))
double code(double x, double y, double z) {
double tmp;
if (y <= -2e-310) {
tmp = (x * (log(-x) - log(-y))) - z;
} else {
tmp = ((x * log(x)) - (x * log(y))) - z;
}
return tmp;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8) :: tmp
if (y <= (-2d-310)) then
tmp = (x * (log(-x) - log(-y))) - z
else
tmp = ((x * log(x)) - (x * log(y))) - z
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (y <= -2e-310) {
tmp = (x * (Math.log(-x) - Math.log(-y))) - z;
} else {
tmp = ((x * Math.log(x)) - (x * Math.log(y))) - z;
}
return tmp;
}
def code(x, y, z): tmp = 0 if y <= -2e-310: tmp = (x * (math.log(-x) - math.log(-y))) - z else: tmp = ((x * math.log(x)) - (x * math.log(y))) - z return tmp
function code(x, y, z) tmp = 0.0 if (y <= -2e-310) tmp = Float64(Float64(x * Float64(log(Float64(-x)) - log(Float64(-y)))) - z); else tmp = Float64(Float64(Float64(x * log(x)) - Float64(x * log(y))) - z); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (y <= -2e-310) tmp = (x * (log(-x) - log(-y))) - z; else tmp = ((x * log(x)) - (x * log(y))) - z; end tmp_2 = tmp; end
code[x_, y_, z_] := If[LessEqual[y, -2e-310], N[(N[(x * N[(N[Log[(-x)], $MachinePrecision] - N[Log[(-y)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], N[(N[(N[(x * N[Log[x], $MachinePrecision]), $MachinePrecision] - N[(x * N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -2 \cdot 10^{-310}:\\
\;\;\;\;x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right) - z\\
\mathbf{else}:\\
\;\;\;\;\left(x \cdot \log x - x \cdot \log y\right) - z\\
\end{array}
\end{array}
if y < -1.999999999999994e-310Initial program 90.9%
frac-2neg90.9%
log-div99.6%
Applied egg-rr99.6%
if -1.999999999999994e-310 < y Initial program 83.0%
add-cube-cbrt83.0%
log-prod82.9%
pow282.9%
Applied egg-rr82.9%
log-pow82.9%
distribute-lft1-in82.9%
metadata-eval82.9%
*-commutative82.9%
Simplified82.9%
Applied egg-rr99.5%
Final simplification99.5%
(FPCore (x y z) :precision binary64 (if (<= y 4.5e-287) (- (* x (log (/ x y))) z) (- (* x (- (log x) (log y))) z)))
double code(double x, double y, double z) {
double tmp;
if (y <= 4.5e-287) {
tmp = (x * log((x / y))) - z;
} else {
tmp = (x * (log(x) - log(y))) - z;
}
return tmp;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8) :: tmp
if (y <= 4.5d-287) then
tmp = (x * log((x / y))) - z
else
tmp = (x * (log(x) - log(y))) - z
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (y <= 4.5e-287) {
tmp = (x * Math.log((x / y))) - z;
} else {
tmp = (x * (Math.log(x) - Math.log(y))) - z;
}
return tmp;
}
def code(x, y, z): tmp = 0 if y <= 4.5e-287: tmp = (x * math.log((x / y))) - z else: tmp = (x * (math.log(x) - math.log(y))) - z return tmp
function code(x, y, z) tmp = 0.0 if (y <= 4.5e-287) tmp = Float64(Float64(x * log(Float64(x / y))) - z); else tmp = Float64(Float64(x * Float64(log(x) - log(y))) - z); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (y <= 4.5e-287) tmp = (x * log((x / y))) - z; else tmp = (x * (log(x) - log(y))) - z; end tmp_2 = tmp; end
code[x_, y_, z_] := If[LessEqual[y, 4.5e-287], N[(N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], N[(N[(x * N[(N[Log[x], $MachinePrecision] - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq 4.5 \cdot 10^{-287}:\\
\;\;\;\;x \cdot \log \left(\frac{x}{y}\right) - z\\
\mathbf{else}:\\
\;\;\;\;x \cdot \left(\log x - \log y\right) - z\\
\end{array}
\end{array}
if y < 4.50000000000000017e-287Initial program 91.3%
if 4.50000000000000017e-287 < y Initial program 82.5%
log-div99.5%
Applied egg-rr99.5%
Final simplification95.9%
(FPCore (x y z) :precision binary64 (- (* x (log (/ x y))) z))
double code(double x, double y, double z) {
return (x * log((x / y))) - z;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = (x * log((x / y))) - z
end function
public static double code(double x, double y, double z) {
return (x * Math.log((x / y))) - z;
}
def code(x, y, z): return (x * math.log((x / y))) - z
function code(x, y, z) return Float64(Float64(x * log(Float64(x / y))) - z) end
function tmp = code(x, y, z) tmp = (x * log((x / y))) - z; end
code[x_, y_, z_] := N[(N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \log \left(\frac{x}{y}\right) - z
\end{array}
Initial program 86.4%
Final simplification86.4%
(FPCore (x y z) :precision binary64 (if (< y 7.595077799083773e-308) (- (* x (log (/ x y))) z) (- (* x (- (log x) (log y))) z)))
double code(double x, double y, double z) {
double tmp;
if (y < 7.595077799083773e-308) {
tmp = (x * log((x / y))) - z;
} else {
tmp = (x * (log(x) - log(y))) - z;
}
return tmp;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8) :: tmp
if (y < 7.595077799083773d-308) then
tmp = (x * log((x / y))) - z
else
tmp = (x * (log(x) - log(y))) - z
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if (y < 7.595077799083773e-308) {
tmp = (x * Math.log((x / y))) - z;
} else {
tmp = (x * (Math.log(x) - Math.log(y))) - z;
}
return tmp;
}
def code(x, y, z): tmp = 0 if y < 7.595077799083773e-308: tmp = (x * math.log((x / y))) - z else: tmp = (x * (math.log(x) - math.log(y))) - z return tmp
function code(x, y, z) tmp = 0.0 if (y < 7.595077799083773e-308) tmp = Float64(Float64(x * log(Float64(x / y))) - z); else tmp = Float64(Float64(x * Float64(log(x) - log(y))) - z); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if (y < 7.595077799083773e-308) tmp = (x * log((x / y))) - z; else tmp = (x * (log(x) - log(y))) - z; end tmp_2 = tmp; end
code[x_, y_, z_] := If[Less[y, 7.595077799083773e-308], N[(N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], N[(N[(x * N[(N[Log[x], $MachinePrecision] - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y < 7.595077799083773 \cdot 10^{-308}:\\
\;\;\;\;x \cdot \log \left(\frac{x}{y}\right) - z\\
\mathbf{else}:\\
\;\;\;\;x \cdot \left(\log x - \log y\right) - z\\
\end{array}
\end{array}
herbie shell --seed 2023271
(FPCore (x y z)
:name "Numeric.SpecFunctions.Extra:bd0 from math-functions-0.1.5.2"
:precision binary64
:herbie-target
(if (< y 7.595077799083773e-308) (- (* x (log (/ x y))) z) (- (* x (- (log x) (log y))) z))
(- (* x (log (/ x y))) z))