
(FPCore (u1 u2) :precision binary64 (+ (* (* (/ 1.0 6.0) (pow (* -2.0 (log u1)) 0.5)) (cos (* (* 2.0 PI) u2))) 0.5))
double code(double u1, double u2) {
return (((1.0 / 6.0) * pow((-2.0 * log(u1)), 0.5)) * cos(((2.0 * ((double) M_PI)) * u2))) + 0.5;
}
public static double code(double u1, double u2) {
return (((1.0 / 6.0) * Math.pow((-2.0 * Math.log(u1)), 0.5)) * Math.cos(((2.0 * Math.PI) * u2))) + 0.5;
}
def code(u1, u2): return (((1.0 / 6.0) * math.pow((-2.0 * math.log(u1)), 0.5)) * math.cos(((2.0 * math.pi) * u2))) + 0.5
function code(u1, u2) return Float64(Float64(Float64(Float64(1.0 / 6.0) * (Float64(-2.0 * log(u1)) ^ 0.5)) * cos(Float64(Float64(2.0 * pi) * u2))) + 0.5) end
function tmp = code(u1, u2) tmp = (((1.0 / 6.0) * ((-2.0 * log(u1)) ^ 0.5)) * cos(((2.0 * pi) * u2))) + 0.5; end
code[u1_, u2_] := N[(N[(N[(N[(1.0 / 6.0), $MachinePrecision] * N[Power[N[(-2.0 * N[Log[u1], $MachinePrecision]), $MachinePrecision], 0.5], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(N[(2.0 * Pi), $MachinePrecision] * u2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{1}{6} \cdot {\left(-2 \cdot \log u1\right)}^{0.5}\right) \cdot \cos \left(\left(2 \cdot \pi\right) \cdot u2\right) + 0.5
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (u1 u2) :precision binary64 (+ (* (* (/ 1.0 6.0) (pow (* -2.0 (log u1)) 0.5)) (cos (* (* 2.0 PI) u2))) 0.5))
double code(double u1, double u2) {
return (((1.0 / 6.0) * pow((-2.0 * log(u1)), 0.5)) * cos(((2.0 * ((double) M_PI)) * u2))) + 0.5;
}
public static double code(double u1, double u2) {
return (((1.0 / 6.0) * Math.pow((-2.0 * Math.log(u1)), 0.5)) * Math.cos(((2.0 * Math.PI) * u2))) + 0.5;
}
def code(u1, u2): return (((1.0 / 6.0) * math.pow((-2.0 * math.log(u1)), 0.5)) * math.cos(((2.0 * math.pi) * u2))) + 0.5
function code(u1, u2) return Float64(Float64(Float64(Float64(1.0 / 6.0) * (Float64(-2.0 * log(u1)) ^ 0.5)) * cos(Float64(Float64(2.0 * pi) * u2))) + 0.5) end
function tmp = code(u1, u2) tmp = (((1.0 / 6.0) * ((-2.0 * log(u1)) ^ 0.5)) * cos(((2.0 * pi) * u2))) + 0.5; end
code[u1_, u2_] := N[(N[(N[(N[(1.0 / 6.0), $MachinePrecision] * N[Power[N[(-2.0 * N[Log[u1], $MachinePrecision]), $MachinePrecision], 0.5], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(N[(2.0 * Pi), $MachinePrecision] * u2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{1}{6} \cdot {\left(-2 \cdot \log u1\right)}^{0.5}\right) \cdot \cos \left(\left(2 \cdot \pi\right) \cdot u2\right) + 0.5
\end{array}
(FPCore (u1 u2) :precision binary64 (+ 0.5 (* (* (sqrt (log (/ 1.0 u1))) (sqrt 2.0)) (* 0.16666666666666666 (cos (* 2.0 (* PI u2)))))))
double code(double u1, double u2) {
return 0.5 + ((sqrt(log((1.0 / u1))) * sqrt(2.0)) * (0.16666666666666666 * cos((2.0 * (((double) M_PI) * u2)))));
}
public static double code(double u1, double u2) {
return 0.5 + ((Math.sqrt(Math.log((1.0 / u1))) * Math.sqrt(2.0)) * (0.16666666666666666 * Math.cos((2.0 * (Math.PI * u2)))));
}
def code(u1, u2): return 0.5 + ((math.sqrt(math.log((1.0 / u1))) * math.sqrt(2.0)) * (0.16666666666666666 * math.cos((2.0 * (math.pi * u2)))))
function code(u1, u2) return Float64(0.5 + Float64(Float64(sqrt(log(Float64(1.0 / u1))) * sqrt(2.0)) * Float64(0.16666666666666666 * cos(Float64(2.0 * Float64(pi * u2)))))) end
function tmp = code(u1, u2) tmp = 0.5 + ((sqrt(log((1.0 / u1))) * sqrt(2.0)) * (0.16666666666666666 * cos((2.0 * (pi * u2))))); end
code[u1_, u2_] := N[(0.5 + N[(N[(N[Sqrt[N[Log[N[(1.0 / u1), $MachinePrecision]], $MachinePrecision]], $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * N[(0.16666666666666666 * N[Cos[N[(2.0 * N[(Pi * u2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 + \left(\sqrt{\log \left(\frac{1}{u1}\right)} \cdot \sqrt{2}\right) \cdot \left(0.16666666666666666 \cdot \cos \left(2 \cdot \left(\pi \cdot u2\right)\right)\right)
\end{array}
Initial program 99.4%
+-commutativeN/A
+-lowering-+.f64N/A
associate-*l*N/A
*-commutativeN/A
associate-*l*N/A
*-lowering-*.f64N/A
unpow1/2N/A
sqrt-lowering-sqrt.f64N/A
*-lowering-*.f64N/A
log-lowering-log.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
metadata-evalN/A
cos-lowering-cos.f64N/A
associate-*l*N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
PI-lowering-PI.f6499.4%
Simplified99.4%
pow1/2N/A
pow-to-expN/A
exp-lowering-exp.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
rem-square-sqrtN/A
log-lowering-log.f64N/A
rem-square-sqrtN/A
*-lowering-*.f64N/A
log-lowering-log.f6498.9%
Applied egg-rr98.9%
Taylor expanded in u1 around inf
*-lowering-*.f64N/A
sqrt-lowering-sqrt.f64N/A
log-lowering-log.f64N/A
/-lowering-/.f64N/A
sqrt-lowering-sqrt.f6499.5%
Simplified99.5%
(FPCore (u1 u2) :precision binary64 (+ 0.5 (* (* 0.16666666666666666 (cos (* 2.0 (* PI u2)))) (sqrt (* -2.0 (log u1))))))
double code(double u1, double u2) {
return 0.5 + ((0.16666666666666666 * cos((2.0 * (((double) M_PI) * u2)))) * sqrt((-2.0 * log(u1))));
}
public static double code(double u1, double u2) {
return 0.5 + ((0.16666666666666666 * Math.cos((2.0 * (Math.PI * u2)))) * Math.sqrt((-2.0 * Math.log(u1))));
}
def code(u1, u2): return 0.5 + ((0.16666666666666666 * math.cos((2.0 * (math.pi * u2)))) * math.sqrt((-2.0 * math.log(u1))))
function code(u1, u2) return Float64(0.5 + Float64(Float64(0.16666666666666666 * cos(Float64(2.0 * Float64(pi * u2)))) * sqrt(Float64(-2.0 * log(u1))))) end
function tmp = code(u1, u2) tmp = 0.5 + ((0.16666666666666666 * cos((2.0 * (pi * u2)))) * sqrt((-2.0 * log(u1)))); end
code[u1_, u2_] := N[(0.5 + N[(N[(0.16666666666666666 * N[Cos[N[(2.0 * N[(Pi * u2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sqrt[N[(-2.0 * N[Log[u1], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 + \left(0.16666666666666666 \cdot \cos \left(2 \cdot \left(\pi \cdot u2\right)\right)\right) \cdot \sqrt{-2 \cdot \log u1}
\end{array}
Initial program 99.4%
+-commutativeN/A
+-lowering-+.f64N/A
associate-*l*N/A
*-commutativeN/A
associate-*l*N/A
*-lowering-*.f64N/A
unpow1/2N/A
sqrt-lowering-sqrt.f64N/A
*-lowering-*.f64N/A
log-lowering-log.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
metadata-evalN/A
cos-lowering-cos.f64N/A
associate-*l*N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
PI-lowering-PI.f6499.4%
Simplified99.4%
Final simplification99.4%
(FPCore (u1 u2) :precision binary64 (+ 0.5 (* (sqrt (- 0.0 (log u1))) (* (sqrt 2.0) 0.16666666666666666))))
double code(double u1, double u2) {
return 0.5 + (sqrt((0.0 - log(u1))) * (sqrt(2.0) * 0.16666666666666666));
}
real(8) function code(u1, u2)
real(8), intent (in) :: u1
real(8), intent (in) :: u2
code = 0.5d0 + (sqrt((0.0d0 - log(u1))) * (sqrt(2.0d0) * 0.16666666666666666d0))
end function
public static double code(double u1, double u2) {
return 0.5 + (Math.sqrt((0.0 - Math.log(u1))) * (Math.sqrt(2.0) * 0.16666666666666666));
}
def code(u1, u2): return 0.5 + (math.sqrt((0.0 - math.log(u1))) * (math.sqrt(2.0) * 0.16666666666666666))
function code(u1, u2) return Float64(0.5 + Float64(sqrt(Float64(0.0 - log(u1))) * Float64(sqrt(2.0) * 0.16666666666666666))) end
function tmp = code(u1, u2) tmp = 0.5 + (sqrt((0.0 - log(u1))) * (sqrt(2.0) * 0.16666666666666666)); end
code[u1_, u2_] := N[(0.5 + N[(N[Sqrt[N[(0.0 - N[Log[u1], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[(N[Sqrt[2.0], $MachinePrecision] * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 + \sqrt{0 - \log u1} \cdot \left(\sqrt{2} \cdot 0.16666666666666666\right)
\end{array}
Initial program 99.4%
+-commutativeN/A
+-lowering-+.f64N/A
associate-*l*N/A
*-commutativeN/A
associate-*l*N/A
*-lowering-*.f64N/A
unpow1/2N/A
sqrt-lowering-sqrt.f64N/A
*-lowering-*.f64N/A
log-lowering-log.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
metadata-evalN/A
cos-lowering-cos.f64N/A
associate-*l*N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
PI-lowering-PI.f6499.4%
Simplified99.4%
pow1/2N/A
pow-to-expN/A
exp-lowering-exp.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
rem-square-sqrtN/A
log-lowering-log.f64N/A
rem-square-sqrtN/A
*-lowering-*.f64N/A
log-lowering-log.f6498.9%
Applied egg-rr98.9%
Taylor expanded in u1 around inf
*-lowering-*.f64N/A
sqrt-lowering-sqrt.f64N/A
log-lowering-log.f64N/A
/-lowering-/.f64N/A
sqrt-lowering-sqrt.f6499.5%
Simplified99.5%
Taylor expanded in u2 around 0
+-lowering-+.f64N/A
*-commutativeN/A
associate-*l*N/A
*-lowering-*.f64N/A
sqrt-lowering-sqrt.f64N/A
log-lowering-log.f64N/A
/-lowering-/.f64N/A
*-lowering-*.f64N/A
sqrt-lowering-sqrt.f6498.7%
Simplified98.7%
log-recN/A
neg-lowering-neg.f64N/A
log-lowering-log.f6498.7%
Applied egg-rr98.7%
Final simplification98.7%
(FPCore (u1 u2) :precision binary64 (+ 0.5 (* 0.16666666666666666 (sqrt (* -2.0 (log u1))))))
double code(double u1, double u2) {
return 0.5 + (0.16666666666666666 * sqrt((-2.0 * log(u1))));
}
real(8) function code(u1, u2)
real(8), intent (in) :: u1
real(8), intent (in) :: u2
code = 0.5d0 + (0.16666666666666666d0 * sqrt(((-2.0d0) * log(u1))))
end function
public static double code(double u1, double u2) {
return 0.5 + (0.16666666666666666 * Math.sqrt((-2.0 * Math.log(u1))));
}
def code(u1, u2): return 0.5 + (0.16666666666666666 * math.sqrt((-2.0 * math.log(u1))))
function code(u1, u2) return Float64(0.5 + Float64(0.16666666666666666 * sqrt(Float64(-2.0 * log(u1))))) end
function tmp = code(u1, u2) tmp = 0.5 + (0.16666666666666666 * sqrt((-2.0 * log(u1)))); end
code[u1_, u2_] := N[(0.5 + N[(0.16666666666666666 * N[Sqrt[N[(-2.0 * N[Log[u1], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 + 0.16666666666666666 \cdot \sqrt{-2 \cdot \log u1}
\end{array}
Initial program 99.4%
+-commutativeN/A
+-lowering-+.f64N/A
associate-*l*N/A
*-commutativeN/A
associate-*l*N/A
*-lowering-*.f64N/A
unpow1/2N/A
sqrt-lowering-sqrt.f64N/A
*-lowering-*.f64N/A
log-lowering-log.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
metadata-evalN/A
cos-lowering-cos.f64N/A
associate-*l*N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
PI-lowering-PI.f6499.4%
Simplified99.4%
Taylor expanded in u2 around 0
+-lowering-+.f64N/A
associate-*r*N/A
*-commutativeN/A
associate-*l*N/A
*-lowering-*.f64N/A
sqrt-lowering-sqrt.f64N/A
log-lowering-log.f64N/A
*-lowering-*.f64N/A
sqrt-lowering-sqrt.f640.0%
Simplified0.0%
+-commutativeN/A
+-lowering-+.f64N/A
*-commutativeN/A
associate-*l*N/A
sqrt-prodN/A
*-lowering-*.f64N/A
sqrt-lowering-sqrt.f64N/A
*-lowering-*.f64N/A
log-lowering-log.f6498.5%
Applied egg-rr98.5%
Final simplification98.5%
herbie shell --seed 2024170
(FPCore (u1 u2)
:name "normal distribution"
:precision binary64
:pre (and (and (<= 0.0 u1) (<= u1 1.0)) (and (<= 0.0 u2) (<= u2 1.0)))
(+ (* (* (/ 1.0 6.0) (pow (* -2.0 (log u1)) 0.5)) (cos (* (* 2.0 PI) u2))) 0.5))