
(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 79.4%
add-cube-cbrt79.4%
pow379.4%
log-pow79.4%
Applied egg-rr79.4%
*-commutative79.4%
Simplified79.4%
cbrt-div99.8%
div-inv99.8%
Applied egg-rr99.8%
associate-*r/99.8%
*-rgt-identity99.8%
Simplified99.8%
Final simplification99.8%
(FPCore (x y z)
:precision binary64
(let* ((t_0 (* x (log (/ x y)))))
(if (<= t_0 (- INFINITY))
(- (* x (log (* x y))) z)
(if (<= t_0 1e+283) (- t_0 z) (- (* x (- (log x) (log y))) 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 if (t_0 <= 1e+283) {
tmp = t_0 - z;
} else {
tmp = (x * (log(x) - log(y))) - 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 if (t_0 <= 1e+283) {
tmp = t_0 - z;
} else {
tmp = (x * (Math.log(x) - Math.log(y))) - 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 elif t_0 <= 1e+283: tmp = t_0 - z else: tmp = (x * (math.log(x) - math.log(y))) - 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); elseif (t_0 <= 1e+283) tmp = Float64(t_0 - z); else tmp = Float64(Float64(x * Float64(log(x) - log(y))) - 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; elseif (t_0 <= 1e+283) tmp = t_0 - z; else tmp = (x * (log(x) - log(y))) - 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], If[LessEqual[t$95$0, 1e+283], N[(t$95$0 - z), $MachinePrecision], N[(N[(x * N[(N[Log[x], $MachinePrecision] - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 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{elif}\;t\_0 \leq 10^{+283}:\\
\;\;\;\;t\_0 - z\\
\mathbf{else}:\\
\;\;\;\;x \cdot \left(\log x - \log y\right) - z\\
\end{array}
\end{array}
if (*.f64 x (log.f64 (/.f64 x y))) < -inf.0Initial program 4.4%
add-cube-cbrt4.4%
pow34.4%
log-pow4.4%
Applied egg-rr4.4%
*-commutative4.4%
Simplified4.4%
add-log-exp4.4%
exp-to-pow4.4%
pow34.4%
add-cube-cbrt4.4%
frac-2neg4.4%
diff-log57.4%
sub-neg57.4%
distribute-rgt-in57.4%
add-sqr-sqrt57.4%
sqrt-unprod14.8%
sqr-neg14.8%
sqrt-unprod0.0%
add-sqr-sqrt0.0%
Applied egg-rr42.4%
distribute-rgt-out42.4%
sub-neg42.4%
log-div4.4%
*-commutative4.4%
clear-num4.4%
associate-/r/4.4%
add-exp-log1.2%
rec-exp1.2%
add-sqr-sqrt0.0%
sqrt-unprod39.9%
sqr-neg39.9%
sqrt-unprod39.9%
add-sqr-sqrt39.9%
add-exp-log59.6%
Applied egg-rr59.6%
if -inf.0 < (*.f64 x (log.f64 (/.f64 x y))) < 9.99999999999999955e282Initial program 99.8%
if 9.99999999999999955e282 < (*.f64 x (log.f64 (/.f64 x y))) Initial program 5.7%
Taylor expanded in x around 0 59.0%
log-rec59.0%
sub-neg59.0%
Simplified59.0%
Final simplification91.1%
(FPCore (x y z)
:precision binary64
(let* ((t_0 (* x (log (/ x y)))))
(if (or (<= t_0 (- INFINITY)) (not (<= t_0 1e+283)))
(- (* 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)) || !(t_0 <= 1e+283)) {
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) || !(t_0 <= 1e+283)) {
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) or not (t_0 <= 1e+283): 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)) || !(t_0 <= 1e+283)) 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) || ~((t_0 <= 1e+283))) 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[Or[LessEqual[t$95$0, (-Infinity)], N[Not[LessEqual[t$95$0, 1e+283]], $MachinePrecision]], 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 \lor \neg \left(t\_0 \leq 10^{+283}\right):\\
\;\;\;\;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.0 or 9.99999999999999955e282 < (*.f64 x (log.f64 (/.f64 x y))) Initial program 4.9%
add-cube-cbrt4.9%
pow34.9%
log-pow4.9%
Applied egg-rr4.9%
*-commutative4.9%
Simplified4.9%
add-log-exp4.9%
exp-to-pow4.9%
pow34.9%
add-cube-cbrt4.9%
frac-2neg4.9%
diff-log50.8%
sub-neg50.8%
distribute-rgt-in50.8%
add-sqr-sqrt50.8%
sqrt-unprod18.2%
sqr-neg18.2%
sqrt-unprod0.0%
add-sqr-sqrt0.0%
Applied egg-rr49.1%
distribute-rgt-out49.0%
sub-neg49.0%
log-div4.9%
*-commutative4.9%
clear-num4.9%
associate-/r/4.9%
add-exp-log2.5%
rec-exp2.5%
add-sqr-sqrt1.8%
sqrt-unprod25.7%
sqr-neg25.7%
sqrt-unprod23.9%
add-sqr-sqrt28.5%
add-exp-log53.7%
Applied egg-rr53.7%
if -inf.0 < (*.f64 x (log.f64 (/.f64 x y))) < 9.99999999999999955e282Initial program 99.8%
Final simplification89.9%
(FPCore (x y z) :precision binary64 (if (<= y -5e-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 <= -5e-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 <= (-5d-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 <= -5e-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 <= -5e-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 <= -5e-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 <= -5e-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, -5e-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 -5 \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 < -4.999999999999985e-310Initial program 79.6%
Taylor expanded in x around -inf 99.7%
+-commutative99.7%
metadata-eval99.7%
distribute-neg-frac99.7%
distribute-frac-neg299.7%
log-rec99.7%
unsub-neg99.7%
mul-1-neg99.7%
metadata-eval99.7%
distribute-neg-frac99.7%
distribute-frac-neg299.7%
log-rec99.7%
neg-mul-199.7%
remove-double-neg99.7%
neg-mul-199.7%
Simplified99.7%
if -4.999999999999985e-310 < y Initial program 79.2%
Taylor expanded in x around 0 99.5%
log-rec99.5%
sub-neg99.5%
Simplified99.5%
Final simplification99.6%
(FPCore (x y z) :precision binary64 (if (<= y -5e-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 <= -5e-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 <= (-5d-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 <= -5e-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 <= -5e-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 <= -5e-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 <= -5e-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, -5e-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 -5 \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 < -4.999999999999985e-310Initial program 79.6%
Taylor expanded in x around -inf 99.7%
+-commutative99.7%
metadata-eval99.7%
distribute-neg-frac99.7%
distribute-frac-neg299.7%
log-rec99.7%
unsub-neg99.7%
mul-1-neg99.7%
metadata-eval99.7%
distribute-neg-frac99.7%
distribute-frac-neg299.7%
log-rec99.7%
neg-mul-199.7%
remove-double-neg99.7%
neg-mul-199.7%
Simplified99.7%
if -4.999999999999985e-310 < y Initial program 79.2%
add-cube-cbrt79.1%
pow379.2%
log-pow79.1%
Applied egg-rr79.1%
*-commutative79.1%
Simplified79.1%
add-log-exp79.1%
exp-to-pow79.2%
pow379.1%
add-cube-cbrt79.2%
frac-2neg79.2%
diff-log0.0%
sub-neg0.0%
distribute-rgt-in0.0%
add-sqr-sqrt0.0%
sqrt-unprod0.0%
sqr-neg0.0%
sqrt-unprod0.0%
add-sqr-sqrt0.0%
Applied egg-rr99.5%
Final simplification99.6%
(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 79.4%
Final simplification79.4%
(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 2024066
(FPCore (x y z)
:name "Numeric.SpecFunctions.Extra:bd0 from math-functions-0.1.5.2"
:precision binary64
:alt
(if (< y 7.595077799083773e-308) (- (* x (log (/ x y))) z) (- (* x (- (log x) (log y))) z))
(- (* x (log (/ x y))) z))