
(FPCore (x) :precision binary32 (acosh x))
float code(float x) {
return acoshf(x);
}
function code(x) return acosh(x) end
function tmp = code(x) tmp = acosh(x); end
\begin{array}{l}
\\
\cosh^{-1} x
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 7 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary32 (log (+ x (sqrt (- (* x x) 1.0)))))
float code(float x) {
return logf((x + sqrtf(((x * x) - 1.0f))));
}
real(4) function code(x)
real(4), intent (in) :: x
code = log((x + sqrt(((x * x) - 1.0e0))))
end function
function code(x) return log(Float32(x + sqrt(Float32(Float32(x * x) - Float32(1.0))))) end
function tmp = code(x) tmp = log((x + sqrt(((x * x) - single(1.0))))); end
\begin{array}{l}
\\
\log \left(x + \sqrt{x \cdot x - 1}\right)
\end{array}
(FPCore (x) :precision binary32 (log (- (- (* x 2.0) (/ 0.0625 (pow x 5.0))) (+ (/ 0.5 x) (/ 0.125 (pow x 3.0))))))
float code(float x) {
return logf((((x * 2.0f) - (0.0625f / powf(x, 5.0f))) - ((0.5f / x) + (0.125f / powf(x, 3.0f)))));
}
real(4) function code(x)
real(4), intent (in) :: x
code = log((((x * 2.0e0) - (0.0625e0 / (x ** 5.0e0))) - ((0.5e0 / x) + (0.125e0 / (x ** 3.0e0)))))
end function
function code(x) return log(Float32(Float32(Float32(x * Float32(2.0)) - Float32(Float32(0.0625) / (x ^ Float32(5.0)))) - Float32(Float32(Float32(0.5) / x) + Float32(Float32(0.125) / (x ^ Float32(3.0)))))) end
function tmp = code(x) tmp = log((((x * single(2.0)) - (single(0.0625) / (x ^ single(5.0)))) - ((single(0.5) / x) + (single(0.125) / (x ^ single(3.0)))))); end
\begin{array}{l}
\\
\log \left(\left(x \cdot 2 - \frac{0.0625}{{x}^{5}}\right) - \left(\frac{0.5}{x} + \frac{0.125}{{x}^{3}}\right)\right)
\end{array}
Initial program 52.1%
Taylor expanded in x around inf 99.0%
associate--r+99.0%
*-commutative99.0%
associate-*r/99.0%
metadata-eval99.0%
+-commutative99.0%
associate-*r/99.0%
metadata-eval99.0%
associate-*r/99.0%
metadata-eval99.0%
Simplified99.0%
Final simplification99.0%
(FPCore (x) :precision binary32 (log1p (+ (* x 2.0) (- -1.0 (+ (/ 0.5 x) (/ 0.125 (pow x 3.0)))))))
float code(float x) {
return log1pf(((x * 2.0f) + (-1.0f - ((0.5f / x) + (0.125f / powf(x, 3.0f))))));
}
function code(x) return log1p(Float32(Float32(x * Float32(2.0)) + Float32(Float32(-1.0) - Float32(Float32(Float32(0.5) / x) + Float32(Float32(0.125) / (x ^ Float32(3.0))))))) end
\begin{array}{l}
\\
\mathsf{log1p}\left(x \cdot 2 + \left(-1 - \left(\frac{0.5}{x} + \frac{0.125}{{x}^{3}}\right)\right)\right)
\end{array}
Initial program 52.1%
log1p-expm1-u52.1%
expm1-undefine52.1%
add-exp-log52.1%
fma-neg52.1%
metadata-eval52.1%
Applied egg-rr52.1%
Taylor expanded in x around inf 98.9%
Taylor expanded in x around 0 98.9%
associate-*r/98.9%
metadata-eval98.9%
associate-*r/98.9%
metadata-eval98.9%
Simplified98.9%
Final simplification98.9%
(FPCore (x) :precision binary32 (log (+ x (- x (/ 0.5 x)))))
float code(float x) {
return logf((x + (x - (0.5f / x))));
}
real(4) function code(x)
real(4), intent (in) :: x
code = log((x + (x - (0.5e0 / x))))
end function
function code(x) return log(Float32(x + Float32(x - Float32(Float32(0.5) / x)))) end
function tmp = code(x) tmp = log((x + (x - (single(0.5) / x)))); end
\begin{array}{l}
\\
\log \left(x + \left(x - \frac{0.5}{x}\right)\right)
\end{array}
Initial program 52.1%
Taylor expanded in x around inf 98.5%
associate-*r/98.5%
metadata-eval98.5%
Simplified98.5%
Final simplification98.5%
(FPCore (x) :precision binary32 (log (- (* x 2.0) (/ 0.5 x))))
float code(float x) {
return logf(((x * 2.0f) - (0.5f / x)));
}
real(4) function code(x)
real(4), intent (in) :: x
code = log(((x * 2.0e0) - (0.5e0 / x)))
end function
function code(x) return log(Float32(Float32(x * Float32(2.0)) - Float32(Float32(0.5) / x))) end
function tmp = code(x) tmp = log(((x * single(2.0)) - (single(0.5) / x))); end
\begin{array}{l}
\\
\log \left(x \cdot 2 - \frac{0.5}{x}\right)
\end{array}
Initial program 52.1%
Taylor expanded in x around inf 98.5%
*-commutative98.5%
associate-*r/98.5%
metadata-eval98.5%
Simplified98.5%
Final simplification98.5%
(FPCore (x) :precision binary32 (log (+ x x)))
float code(float x) {
return logf((x + x));
}
real(4) function code(x)
real(4), intent (in) :: x
code = log((x + x))
end function
function code(x) return log(Float32(x + x)) end
function tmp = code(x) tmp = log((x + x)); end
\begin{array}{l}
\\
\log \left(x + x\right)
\end{array}
Initial program 52.1%
Taylor expanded in x around inf 97.0%
Final simplification97.0%
(FPCore (x) :precision binary32 (log x))
float code(float x) {
return logf(x);
}
real(4) function code(x)
real(4), intent (in) :: x
code = log(x)
end function
function code(x) return log(x) end
function tmp = code(x) tmp = log(x); end
\begin{array}{l}
\\
\log x
\end{array}
Initial program 52.1%
Taylor expanded in x around inf 98.5%
associate-*r/98.5%
metadata-eval98.5%
Simplified98.5%
*-un-lft-identity98.5%
fma-define98.5%
clear-num98.5%
div-inv98.5%
metadata-eval98.5%
*-commutative98.5%
count-298.5%
flip-+-0.0%
+-inverses-0.0%
+-inverses-0.0%
+-inverses-0.0%
+-inverses-0.0%
clear-num-0.0%
+-inverses-0.0%
+-inverses-0.0%
Applied egg-rr-0.0%
Simplified43.9%
Taylor expanded in x around inf 44.3%
mul-1-neg44.3%
log-rec44.3%
remove-double-neg44.3%
Simplified44.3%
Final simplification44.3%
(FPCore (x) :precision binary32 -1.0)
float code(float x) {
return -1.0f;
}
real(4) function code(x)
real(4), intent (in) :: x
code = -1.0e0
end function
function code(x) return Float32(-1.0) end
function tmp = code(x) tmp = single(-1.0); end
\begin{array}{l}
\\
-1
\end{array}
Initial program 52.1%
Taylor expanded in x around inf 99.0%
associate--r+99.0%
*-commutative99.0%
associate-*r/99.0%
metadata-eval99.0%
+-commutative99.0%
associate-*r/99.0%
metadata-eval99.0%
associate-*r/99.0%
metadata-eval99.0%
Simplified99.0%
Taylor expanded in x around inf 96.5%
Simplified3.1%
Final simplification3.1%
(FPCore (x) :precision binary32 (log (+ x (* (sqrt (- x 1.0)) (sqrt (+ x 1.0))))))
float code(float x) {
return logf((x + (sqrtf((x - 1.0f)) * sqrtf((x + 1.0f)))));
}
real(4) function code(x)
real(4), intent (in) :: x
code = log((x + (sqrt((x - 1.0e0)) * sqrt((x + 1.0e0)))))
end function
function code(x) return log(Float32(x + Float32(sqrt(Float32(x - Float32(1.0))) * sqrt(Float32(x + Float32(1.0)))))) end
function tmp = code(x) tmp = log((x + (sqrt((x - single(1.0))) * sqrt((x + single(1.0)))))); end
\begin{array}{l}
\\
\log \left(x + \sqrt{x - 1} \cdot \sqrt{x + 1}\right)
\end{array}
herbie shell --seed 2024039
(FPCore (x)
:name "Rust f32::acosh"
:precision binary32
:pre (>= x 1.0)
:herbie-target
(log (+ x (* (sqrt (- x 1.0)) (sqrt (+ x 1.0)))))
(log (+ x (sqrt (- (* x x) 1.0)))))