
(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 3 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 u1) -0.05555555555555555)) (cos (* 2.0 (* PI u2))))))
double code(double u1, double u2) {
return 0.5 + (sqrt((log(u1) * -0.05555555555555555)) * cos((2.0 * (((double) M_PI) * u2))));
}
public static double code(double u1, double u2) {
return 0.5 + (Math.sqrt((Math.log(u1) * -0.05555555555555555)) * Math.cos((2.0 * (Math.PI * u2))));
}
def code(u1, u2): return 0.5 + (math.sqrt((math.log(u1) * -0.05555555555555555)) * math.cos((2.0 * (math.pi * u2))))
function code(u1, u2) return Float64(0.5 + Float64(sqrt(Float64(log(u1) * -0.05555555555555555)) * cos(Float64(2.0 * Float64(pi * u2))))) end
function tmp = code(u1, u2) tmp = 0.5 + (sqrt((log(u1) * -0.05555555555555555)) * cos((2.0 * (pi * u2)))); end
code[u1_, u2_] := N[(0.5 + N[(N[Sqrt[N[(N[Log[u1], $MachinePrecision] * -0.05555555555555555), $MachinePrecision]], $MachinePrecision] * N[Cos[N[(2.0 * N[(Pi * u2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 + \sqrt{\log u1 \cdot -0.05555555555555555} \cdot \cos \left(2 \cdot \left(\pi \cdot u2\right)\right)
\end{array}
Initial program 99.4%
+-commutativeN/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
metadata-evalN/A
unpow1/2N/A
sqrt-lowering-sqrt.f64N/A
*-lowering-*.f64N/A
log-lowering-log.f64N/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
log-lowering-log.f64N/A
*-lowering-*.f64N/A
log-lowering-log.f6498.9%
Applied egg-rr98.9%
*-commutativeN/A
pow-to-expN/A
sqr-powN/A
pow2N/A
pow-lowering-pow.f64N/A
unpow1N/A
metadata-evalN/A
sqrt-pow2N/A
metadata-evalN/A
pow-lowering-pow.f64N/A
sqrt-pow2N/A
metadata-evalN/A
unpow1N/A
*-commutativeN/A
*-lowering-*.f64N/A
log-lowering-log.f6499.0%
Applied egg-rr99.0%
metadata-evalN/A
pow-powN/A
metadata-evalN/A
pow1/2N/A
sqrt-prodN/A
sqrt-lowering-sqrt.f64N/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
metadata-evalN/A
*-lowering-*.f64N/A
log-lowering-log.f64N/A
metadata-eval99.6%
Applied egg-rr99.6%
(FPCore (u1 u2) :precision binary64 (+ 0.5 (* (+ 0.16666666666666666 (* (* u2 u2) (* -0.3333333333333333 (* PI PI)))) (sqrt (* (log u1) -2.0)))))
double code(double u1, double u2) {
return 0.5 + ((0.16666666666666666 + ((u2 * u2) * (-0.3333333333333333 * (((double) M_PI) * ((double) M_PI))))) * sqrt((log(u1) * -2.0)));
}
public static double code(double u1, double u2) {
return 0.5 + ((0.16666666666666666 + ((u2 * u2) * (-0.3333333333333333 * (Math.PI * Math.PI)))) * Math.sqrt((Math.log(u1) * -2.0)));
}
def code(u1, u2): return 0.5 + ((0.16666666666666666 + ((u2 * u2) * (-0.3333333333333333 * (math.pi * math.pi)))) * math.sqrt((math.log(u1) * -2.0)))
function code(u1, u2) return Float64(0.5 + Float64(Float64(0.16666666666666666 + Float64(Float64(u2 * u2) * Float64(-0.3333333333333333 * Float64(pi * pi)))) * sqrt(Float64(log(u1) * -2.0)))) end
function tmp = code(u1, u2) tmp = 0.5 + ((0.16666666666666666 + ((u2 * u2) * (-0.3333333333333333 * (pi * pi)))) * sqrt((log(u1) * -2.0))); end
code[u1_, u2_] := N[(0.5 + N[(N[(0.16666666666666666 + N[(N[(u2 * u2), $MachinePrecision] * N[(-0.3333333333333333 * N[(Pi * Pi), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Sqrt[N[(N[Log[u1], $MachinePrecision] * -2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 + \left(0.16666666666666666 + \left(u2 \cdot u2\right) \cdot \left(-0.3333333333333333 \cdot \left(\pi \cdot \pi\right)\right)\right) \cdot \sqrt{\log u1 \cdot -2}
\end{array}
Initial program 99.4%
+-commutativeN/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
metadata-evalN/A
unpow1/2N/A
sqrt-lowering-sqrt.f64N/A
*-lowering-*.f64N/A
log-lowering-log.f64N/A
cos-lowering-cos.f64N/A
associate-*l*N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
PI-lowering-PI.f6499.4%
Simplified99.4%
associate-*l*N/A
*-commutativeN/A
associate-*r*N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
cos-2N/A
cos-sumN/A
cos-lowering-cos.f64N/A
count-2N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
PI-lowering-PI.f64N/A
sqrt-lowering-sqrt.f64N/A
*-lowering-*.f64N/A
log-lowering-log.f6499.4%
Applied egg-rr99.4%
Taylor expanded in u2 around 0
*-commutativeN/A
associate-*r*N/A
+-lowering-+.f64N/A
associate-*r*N/A
*-commutativeN/A
*-commutativeN/A
associate-*r*N/A
*-commutativeN/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f64N/A
PI-lowering-PI.f64N/A
PI-lowering-PI.f6499.0%
Simplified99.0%
Final simplification99.0%
(FPCore (u1 u2) :precision binary64 (+ 0.5 (sqrt (* (log u1) -0.05555555555555555))))
double code(double u1, double u2) {
return 0.5 + sqrt((log(u1) * -0.05555555555555555));
}
real(8) function code(u1, u2)
real(8), intent (in) :: u1
real(8), intent (in) :: u2
code = 0.5d0 + sqrt((log(u1) * (-0.05555555555555555d0)))
end function
public static double code(double u1, double u2) {
return 0.5 + Math.sqrt((Math.log(u1) * -0.05555555555555555));
}
def code(u1, u2): return 0.5 + math.sqrt((math.log(u1) * -0.05555555555555555))
function code(u1, u2) return Float64(0.5 + sqrt(Float64(log(u1) * -0.05555555555555555))) end
function tmp = code(u1, u2) tmp = 0.5 + sqrt((log(u1) * -0.05555555555555555)); end
code[u1_, u2_] := N[(0.5 + N[Sqrt[N[(N[Log[u1], $MachinePrecision] * -0.05555555555555555), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.5 + \sqrt{\log u1 \cdot -0.05555555555555555}
\end{array}
Initial program 99.4%
+-commutativeN/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
*-lowering-*.f64N/A
metadata-evalN/A
unpow1/2N/A
sqrt-lowering-sqrt.f64N/A
*-lowering-*.f64N/A
log-lowering-log.f64N/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
*-commutativeN/A
associate-*l*N/A
*-commutativeN/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-*r*N/A
sqrt-prodN/A
*-lowering-*.f64N/A
rem-exp-logN/A
sqrt-lowering-sqrt.f64N/A
rem-exp-logN/A
*-lowering-*.f64N/A
log-lowering-log.f6498.2%
Applied egg-rr98.2%
+-lowering-+.f64N/A
unpow1N/A
metadata-evalN/A
pow-prod-upN/A
pow-prod-downN/A
unpow2N/A
pow-lowering-pow.f64N/A
unpow-prod-downN/A
metadata-evalN/A
*-lowering-*.f64N/A
sqrt-pow2N/A
metadata-evalN/A
unpow1N/A
*-commutativeN/A
*-lowering-*.f64N/A
log-lowering-log.f6498.5%
Applied egg-rr98.5%
unpow1/2N/A
sqrt-lowering-sqrt.f64N/A
*-commutativeN/A
associate-*l*N/A
metadata-evalN/A
metadata-evalN/A
*-lowering-*.f64N/A
log-lowering-log.f64N/A
metadata-eval98.5%
Applied egg-rr98.5%
Final simplification98.5%
herbie shell --seed 2024138
(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))