
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (/ u1 (- 1.0 u1))) (cos (* 6.28318530718 u2))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf((u1 / (1.0f - u1))) * cosf((6.28318530718f * u2));
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt((u1 / (1.0e0 - u1))) * cos((6.28318530718e0 * u2))
end function
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(u1 / Float32(Float32(1.0) - u1))) * cos(Float32(Float32(6.28318530718) * u2))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt((u1 / (single(1.0) - u1))) * cos((single(6.28318530718) * u2)); end
\begin{array}{l}
\\
\sqrt{\frac{u1}{1 - u1}} \cdot \cos \left(6.28318530718 \cdot u2\right)
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (/ u1 (- 1.0 u1))) (cos (* 6.28318530718 u2))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf((u1 / (1.0f - u1))) * cosf((6.28318530718f * u2));
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt((u1 / (1.0e0 - u1))) * cos((6.28318530718e0 * u2))
end function
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(u1 / Float32(Float32(1.0) - u1))) * cos(Float32(Float32(6.28318530718) * u2))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt((u1 / (single(1.0) - u1))) * cos((single(6.28318530718) * u2)); end
\begin{array}{l}
\\
\sqrt{\frac{u1}{1 - u1}} \cdot \cos \left(6.28318530718 \cdot u2\right)
\end{array}
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (/ u1 (- 1.0 u1))) (cos (log (+ 1.0 (expm1 (* 6.28318530718 u2)))))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf((u1 / (1.0f - u1))) * cosf(logf((1.0f + expm1f((6.28318530718f * u2)))));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(u1 / Float32(Float32(1.0) - u1))) * cos(log(Float32(Float32(1.0) + expm1(Float32(Float32(6.28318530718) * u2)))))) end
\begin{array}{l}
\\
\sqrt{\frac{u1}{1 - u1}} \cdot \cos \log \left(1 + \mathsf{expm1}\left(6.28318530718 \cdot u2\right)\right)
\end{array}
Initial program 99.0%
log1p-expm1-u99.0%
log1p-udef99.1%
Applied egg-rr99.1%
Final simplification99.1%
(FPCore (cosTheta_i u1 u2) :precision binary32 (if (<= (* 6.28318530718 u2) 0.017999999225139618) (sqrt (/ u1 (- 1.0 u1))) (* (cos (* 6.28318530718 u2)) (sqrt u1))))
float code(float cosTheta_i, float u1, float u2) {
float tmp;
if ((6.28318530718f * u2) <= 0.017999999225139618f) {
tmp = sqrtf((u1 / (1.0f - u1)));
} else {
tmp = cosf((6.28318530718f * u2)) * sqrtf(u1);
}
return tmp;
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
real(4) :: tmp
if ((6.28318530718e0 * u2) <= 0.017999999225139618e0) then
tmp = sqrt((u1 / (1.0e0 - u1)))
else
tmp = cos((6.28318530718e0 * u2)) * sqrt(u1)
end if
code = tmp
end function
function code(cosTheta_i, u1, u2) tmp = Float32(0.0) if (Float32(Float32(6.28318530718) * u2) <= Float32(0.017999999225139618)) tmp = sqrt(Float32(u1 / Float32(Float32(1.0) - u1))); else tmp = Float32(cos(Float32(Float32(6.28318530718) * u2)) * sqrt(u1)); end return tmp end
function tmp_2 = code(cosTheta_i, u1, u2) tmp = single(0.0); if ((single(6.28318530718) * u2) <= single(0.017999999225139618)) tmp = sqrt((u1 / (single(1.0) - u1))); else tmp = cos((single(6.28318530718) * u2)) * sqrt(u1); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;6.28318530718 \cdot u2 \leq 0.017999999225139618:\\
\;\;\;\;\sqrt{\frac{u1}{1 - u1}}\\
\mathbf{else}:\\
\;\;\;\;\cos \left(6.28318530718 \cdot u2\right) \cdot \sqrt{u1}\\
\end{array}
\end{array}
if (*.f32 314159265359/50000000000 u2) < 0.0179999992Initial program 99.6%
Taylor expanded in u2 around 0 95.6%
if 0.0179999992 < (*.f32 314159265359/50000000000 u2) Initial program 97.8%
Taylor expanded in u1 around 0 69.3%
Final simplification87.8%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (/ u1 (- 1.0 u1))) (cos (* 6.28318530718 u2))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf((u1 / (1.0f - u1))) * cosf((6.28318530718f * u2));
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt((u1 / (1.0e0 - u1))) * cos((6.28318530718e0 * u2))
end function
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(u1 / Float32(Float32(1.0) - u1))) * cos(Float32(Float32(6.28318530718) * u2))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt((u1 / (single(1.0) - u1))) * cos((single(6.28318530718) * u2)); end
\begin{array}{l}
\\
\sqrt{\frac{u1}{1 - u1}} \cdot \cos \left(6.28318530718 \cdot u2\right)
\end{array}
Initial program 99.0%
Final simplification99.0%
(FPCore (cosTheta_i u1 u2) :precision binary32 (sqrt (/ u1 (- 1.0 u1))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf((u1 / (1.0f - u1)));
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt((u1 / (1.0e0 - u1)))
end function
function code(cosTheta_i, u1, u2) return sqrt(Float32(u1 / Float32(Float32(1.0) - u1))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt((u1 / (single(1.0) - u1))); end
\begin{array}{l}
\\
\sqrt{\frac{u1}{1 - u1}}
\end{array}
Initial program 99.0%
Taylor expanded in u2 around 0 78.0%
Final simplification78.0%
(FPCore (cosTheta_i u1 u2) :precision binary32 (sqrt u1))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(u1);
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt(u1)
end function
function code(cosTheta_i, u1, u2) return sqrt(u1) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt(u1); end
\begin{array}{l}
\\
\sqrt{u1}
\end{array}
Initial program 99.0%
Taylor expanded in u2 around 0 78.0%
Taylor expanded in u1 around 0 62.5%
Final simplification62.5%
herbie shell --seed 2023308
(FPCore (cosTheta_i u1 u2)
:name "Trowbridge-Reitz Sample, near normal, slope_x"
:precision binary32
:pre (and (and (and (> cosTheta_i 0.9999) (<= cosTheta_i 1.0)) (and (<= 2.328306437e-10 u1) (<= u1 1.0))) (and (<= 2.328306437e-10 u2) (<= u2 1.0)))
(* (sqrt (/ u1 (- 1.0 u1))) (cos (* 6.28318530718 u2))))