
(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 7 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 (if (<= y -4e-311) (- (fma (- (log (- y)) (log (- x))) x z)) (- (* x (- (log x) (log y))) z)))
double code(double x, double y, double z) {
double tmp;
if (y <= -4e-311) {
tmp = -fma((log(-y) - log(-x)), x, z);
} else {
tmp = (x * (log(x) - log(y))) - z;
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (y <= -4e-311) tmp = Float64(-fma(Float64(log(Float64(-y)) - log(Float64(-x))), x, z)); else tmp = Float64(Float64(x * Float64(log(x) - log(y))) - z); end return tmp end
code[x_, y_, z_] := If[LessEqual[y, -4e-311], (-N[(N[(N[Log[(-y)], $MachinePrecision] - N[Log[(-x)], $MachinePrecision]), $MachinePrecision] * x + 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 \cdot 10^{-311}:\\
\;\;\;\;-\mathsf{fma}\left(\log \left(-y\right) - \log \left(-x\right), x, z\right)\\
\mathbf{else}:\\
\;\;\;\;x \cdot \left(\log x - \log y\right) - z\\
\end{array}
\end{array}
if y < -3.99999999999979e-311Initial program 74.8%
Taylor expanded in x around -inf
mul-1-negN/A
lower-neg.f64N/A
distribute-lft-inN/A
fp-cancel-sign-sub-invN/A
distribute-lft-neg-inN/A
*-commutativeN/A
associate-*l/N/A
associate-/l*N/A
distribute-lft-neg-inN/A
*-inversesN/A
fp-cancel-sign-subN/A
*-rgt-identityN/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites99.6%
if -3.99999999999979e-311 < y Initial program 74.8%
lift-log.f64N/A
lift-/.f64N/A
log-divN/A
lower--.f64N/A
lower-log.f64N/A
lower-log.f6499.7
Applied rewrites99.7%
(FPCore (x y z) :precision binary64 (let* ((t_0 (* x (log (/ x y))))) (if (or (<= t_0 (- INFINITY)) (not (<= t_0 5e+306))) (- 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 <= 5e+306)) {
tmp = -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 <= 5e+306)) {
tmp = -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 <= 5e+306): tmp = -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 <= 5e+306)) tmp = Float64(-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 <= 5e+306))) tmp = -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, 5e+306]], $MachinePrecision]], (-z), 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 5 \cdot 10^{+306}\right):\\
\;\;\;\;-z\\
\mathbf{else}:\\
\;\;\;\;t\_0 - z\\
\end{array}
\end{array}
if (*.f64 x (log.f64 (/.f64 x y))) < -inf.0 or 4.99999999999999993e306 < (*.f64 x (log.f64 (/.f64 x y))) Initial program 9.6%
Taylor expanded in x around 0
mul-1-negN/A
lower-neg.f6445.8
Applied rewrites45.8%
if -inf.0 < (*.f64 x (log.f64 (/.f64 x y))) < 4.99999999999999993e306Initial program 99.8%
Final simplification84.8%
(FPCore (x y z)
:precision binary64
(let* ((t_0 (* x (log (/ x y)))))
(if (or (<= t_0 (- INFINITY)) (not (<= t_0 5e+306)))
(- z)
(- (fma (log (/ y x)) x 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 <= 5e+306)) {
tmp = -z;
} else {
tmp = -fma(log((y / x)), x, 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 <= 5e+306)) tmp = Float64(-z); else tmp = Float64(-fma(log(Float64(y / x)), x, z)); end return 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, 5e+306]], $MachinePrecision]], (-z), (-N[(N[Log[N[(y / x), $MachinePrecision]], $MachinePrecision] * x + 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 5 \cdot 10^{+306}\right):\\
\;\;\;\;-z\\
\mathbf{else}:\\
\;\;\;\;-\mathsf{fma}\left(\log \left(\frac{y}{x}\right), x, z\right)\\
\end{array}
\end{array}
if (*.f64 x (log.f64 (/.f64 x y))) < -inf.0 or 4.99999999999999993e306 < (*.f64 x (log.f64 (/.f64 x y))) Initial program 9.6%
Taylor expanded in x around 0
mul-1-negN/A
lower-neg.f6445.8
Applied rewrites45.8%
if -inf.0 < (*.f64 x (log.f64 (/.f64 x y))) < 4.99999999999999993e306Initial program 99.8%
Taylor expanded in x around -inf
mul-1-negN/A
lower-neg.f64N/A
distribute-lft-inN/A
fp-cancel-sign-sub-invN/A
distribute-lft-neg-inN/A
*-commutativeN/A
associate-*l/N/A
associate-/l*N/A
distribute-lft-neg-inN/A
*-inversesN/A
fp-cancel-sign-subN/A
*-rgt-identityN/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites52.2%
Applied rewrites97.7%
Final simplification83.3%
(FPCore (x y z)
:precision binary64
(if (<= x -1.5e+109)
(* (- (log (- x)) (log (- y))) x)
(if (<= x -6e-143)
(- (fma (log (/ y x)) x z))
(if (<= x -4e-308) (- z) (- (* x (- (log x) (log y))) z)))))
double code(double x, double y, double z) {
double tmp;
if (x <= -1.5e+109) {
tmp = (log(-x) - log(-y)) * x;
} else if (x <= -6e-143) {
tmp = -fma(log((y / x)), x, z);
} else if (x <= -4e-308) {
tmp = -z;
} else {
tmp = (x * (log(x) - log(y))) - z;
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (x <= -1.5e+109) tmp = Float64(Float64(log(Float64(-x)) - log(Float64(-y))) * x); elseif (x <= -6e-143) tmp = Float64(-fma(log(Float64(y / x)), x, z)); elseif (x <= -4e-308) tmp = Float64(-z); else tmp = Float64(Float64(x * Float64(log(x) - log(y))) - z); end return tmp end
code[x_, y_, z_] := If[LessEqual[x, -1.5e+109], N[(N[(N[Log[(-x)], $MachinePrecision] - N[Log[(-y)], $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision], If[LessEqual[x, -6e-143], (-N[(N[Log[N[(y / x), $MachinePrecision]], $MachinePrecision] * x + z), $MachinePrecision]), If[LessEqual[x, -4e-308], (-z), N[(N[(x * N[(N[Log[x], $MachinePrecision] - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.5 \cdot 10^{+109}:\\
\;\;\;\;\left(\log \left(-x\right) - \log \left(-y\right)\right) \cdot x\\
\mathbf{elif}\;x \leq -6 \cdot 10^{-143}:\\
\;\;\;\;-\mathsf{fma}\left(\log \left(\frac{y}{x}\right), x, z\right)\\
\mathbf{elif}\;x \leq -4 \cdot 10^{-308}:\\
\;\;\;\;-z\\
\mathbf{else}:\\
\;\;\;\;x \cdot \left(\log x - \log y\right) - z\\
\end{array}
\end{array}
if x < -1.50000000000000008e109Initial program 64.7%
Taylor expanded in x around -inf
*-commutativeN/A
lower-*.f64N/A
Applied rewrites91.0%
if -1.50000000000000008e109 < x < -5.9999999999999997e-143Initial program 92.1%
Taylor expanded in x around -inf
mul-1-negN/A
lower-neg.f64N/A
distribute-lft-inN/A
fp-cancel-sign-sub-invN/A
distribute-lft-neg-inN/A
*-commutativeN/A
associate-*l/N/A
associate-/l*N/A
distribute-lft-neg-inN/A
*-inversesN/A
fp-cancel-sign-subN/A
*-rgt-identityN/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites99.5%
Applied rewrites92.1%
if -5.9999999999999997e-143 < x < -4.00000000000000013e-308Initial program 64.3%
Taylor expanded in x around 0
mul-1-negN/A
lower-neg.f6491.2
Applied rewrites91.2%
if -4.00000000000000013e-308 < x Initial program 74.8%
lift-log.f64N/A
lift-/.f64N/A
log-divN/A
lower--.f64N/A
lower-log.f64N/A
lower-log.f6499.7
Applied rewrites99.7%
(FPCore (x y z) :precision binary64 (if (<= x -6e-143) (- (fma (log (/ y x)) x z)) (if (<= x -4e-308) (- z) (- (* x (- (log x) (log y))) z))))
double code(double x, double y, double z) {
double tmp;
if (x <= -6e-143) {
tmp = -fma(log((y / x)), x, z);
} else if (x <= -4e-308) {
tmp = -z;
} else {
tmp = (x * (log(x) - log(y))) - z;
}
return tmp;
}
function code(x, y, z) tmp = 0.0 if (x <= -6e-143) tmp = Float64(-fma(log(Float64(y / x)), x, z)); elseif (x <= -4e-308) tmp = Float64(-z); else tmp = Float64(Float64(x * Float64(log(x) - log(y))) - z); end return tmp end
code[x_, y_, z_] := If[LessEqual[x, -6e-143], (-N[(N[Log[N[(y / x), $MachinePrecision]], $MachinePrecision] * x + z), $MachinePrecision]), If[LessEqual[x, -4e-308], (-z), N[(N[(x * N[(N[Log[x], $MachinePrecision] - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -6 \cdot 10^{-143}:\\
\;\;\;\;-\mathsf{fma}\left(\log \left(\frac{y}{x}\right), x, z\right)\\
\mathbf{elif}\;x \leq -4 \cdot 10^{-308}:\\
\;\;\;\;-z\\
\mathbf{else}:\\
\;\;\;\;x \cdot \left(\log x - \log y\right) - z\\
\end{array}
\end{array}
if x < -5.9999999999999997e-143Initial program 79.1%
Taylor expanded in x around -inf
mul-1-negN/A
lower-neg.f64N/A
distribute-lft-inN/A
fp-cancel-sign-sub-invN/A
distribute-lft-neg-inN/A
*-commutativeN/A
associate-*l/N/A
associate-/l*N/A
distribute-lft-neg-inN/A
*-inversesN/A
fp-cancel-sign-subN/A
*-rgt-identityN/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites99.4%
Applied rewrites79.1%
if -5.9999999999999997e-143 < x < -4.00000000000000013e-308Initial program 64.3%
Taylor expanded in x around 0
mul-1-negN/A
lower-neg.f6491.2
Applied rewrites91.2%
if -4.00000000000000013e-308 < x Initial program 74.8%
lift-log.f64N/A
lift-/.f64N/A
log-divN/A
lower--.f64N/A
lower-log.f64N/A
lower-log.f6499.7
Applied rewrites99.7%
(FPCore (x y z) :precision binary64 (if (or (<= z -2.4e+34) (not (<= z 5.6e-36))) (- z) (* (log (/ x y)) x)))
double code(double x, double y, double z) {
double tmp;
if ((z <= -2.4e+34) || !(z <= 5.6e-36)) {
tmp = -z;
} else {
tmp = log((x / y)) * x;
}
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 ((z <= (-2.4d+34)) .or. (.not. (z <= 5.6d-36))) then
tmp = -z
else
tmp = log((x / y)) * x
end if
code = tmp
end function
public static double code(double x, double y, double z) {
double tmp;
if ((z <= -2.4e+34) || !(z <= 5.6e-36)) {
tmp = -z;
} else {
tmp = Math.log((x / y)) * x;
}
return tmp;
}
def code(x, y, z): tmp = 0 if (z <= -2.4e+34) or not (z <= 5.6e-36): tmp = -z else: tmp = math.log((x / y)) * x return tmp
function code(x, y, z) tmp = 0.0 if ((z <= -2.4e+34) || !(z <= 5.6e-36)) tmp = Float64(-z); else tmp = Float64(log(Float64(x / y)) * x); end return tmp end
function tmp_2 = code(x, y, z) tmp = 0.0; if ((z <= -2.4e+34) || ~((z <= 5.6e-36))) tmp = -z; else tmp = log((x / y)) * x; end tmp_2 = tmp; end
code[x_, y_, z_] := If[Or[LessEqual[z, -2.4e+34], N[Not[LessEqual[z, 5.6e-36]], $MachinePrecision]], (-z), N[(N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision] * x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;z \leq -2.4 \cdot 10^{+34} \lor \neg \left(z \leq 5.6 \cdot 10^{-36}\right):\\
\;\;\;\;-z\\
\mathbf{else}:\\
\;\;\;\;\log \left(\frac{x}{y}\right) \cdot x\\
\end{array}
\end{array}
if z < -2.39999999999999987e34 or 5.6000000000000002e-36 < z Initial program 71.1%
Taylor expanded in x around 0
mul-1-negN/A
lower-neg.f6477.8
Applied rewrites77.8%
if -2.39999999999999987e34 < z < 5.6000000000000002e-36Initial program 78.7%
Taylor expanded in z around 0
*-commutativeN/A
lower-*.f64N/A
lower-log.f64N/A
lower-/.f6463.1
Applied rewrites63.1%
Final simplification70.6%
(FPCore (x y z) :precision binary64 (- z))
double code(double x, double y, double z) {
return -z;
}
real(8) function code(x, y, z)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
code = -z
end function
public static double code(double x, double y, double z) {
return -z;
}
def code(x, y, z): return -z
function code(x, y, z) return Float64(-z) end
function tmp = code(x, y, z) tmp = -z; end
code[x_, y_, z_] := (-z)
\begin{array}{l}
\\
-z
\end{array}
Initial program 74.8%
Taylor expanded in x around 0
mul-1-negN/A
lower-neg.f6450.6
Applied rewrites50.6%
(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 2024326
(FPCore (x y z)
:name "Numeric.SpecFunctions.Extra:bd0 from math-functions-0.1.5.2"
:precision binary64
:alt
(! :herbie-platform default (if (< y 7595077799083773/100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000) (- (* x (log (/ x y))) z) (- (* x (- (log x) (log y))) z)))
(- (* x (log (/ x y))) z))