
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (* x PI) tau))) (* (/ (sin t_1) t_1) (/ (sin (* x PI)) (* x PI)))))
float code(float x, float tau) {
float t_1 = (x * ((float) M_PI)) * tau;
return (sinf(t_1) / t_1) * (sinf((x * ((float) M_PI))) / (x * ((float) M_PI)));
}
function code(x, tau) t_1 = Float32(Float32(x * Float32(pi)) * tau) return Float32(Float32(sin(t_1) / t_1) * Float32(sin(Float32(x * Float32(pi))) / Float32(x * Float32(pi)))) end
function tmp = code(x, tau) t_1 = (x * single(pi)) * tau; tmp = (sin(t_1) / t_1) * (sin((x * single(pi))) / (x * single(pi))); end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \left(x \cdot \pi\right) \cdot tau\\
\frac{\sin t_1}{t_1} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi}
\end{array}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 11 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (* x PI) tau))) (* (/ (sin t_1) t_1) (/ (sin (* x PI)) (* x PI)))))
float code(float x, float tau) {
float t_1 = (x * ((float) M_PI)) * tau;
return (sinf(t_1) / t_1) * (sinf((x * ((float) M_PI))) / (x * ((float) M_PI)));
}
function code(x, tau) t_1 = Float32(Float32(x * Float32(pi)) * tau) return Float32(Float32(sin(t_1) / t_1) * Float32(sin(Float32(x * Float32(pi))) / Float32(x * Float32(pi)))) end
function tmp = code(x, tau) t_1 = (x * single(pi)) * tau; tmp = (sin(t_1) / t_1) * (sin((x * single(pi))) / (x * single(pi))); end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \left(x \cdot \pi\right) \cdot tau\\
\frac{\sin t_1}{t_1} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi}
\end{array}
\end{array}
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (* x PI) tau))) (* (/ (sin t_1) t_1) (/ (sin (* x PI)) (* x PI)))))
float code(float x, float tau) {
float t_1 = (x * ((float) M_PI)) * tau;
return (sinf(t_1) / t_1) * (sinf((x * ((float) M_PI))) / (x * ((float) M_PI)));
}
function code(x, tau) t_1 = Float32(Float32(x * Float32(pi)) * tau) return Float32(Float32(sin(t_1) / t_1) * Float32(sin(Float32(x * Float32(pi))) / Float32(x * Float32(pi)))) end
function tmp = code(x, tau) t_1 = (x * single(pi)) * tau; tmp = (sin(t_1) / t_1) * (sin((x * single(pi))) / (x * single(pi))); end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \left(x \cdot \pi\right) \cdot tau\\
\frac{\sin t_1}{t_1} \cdot \frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi}
\end{array}
\end{array}
Initial program 98.0%
Final simplification98.0%
(FPCore (x tau) :precision binary32 (* (/ (sin (* x PI)) (* x PI)) (/ (sin (* (* x PI) tau)) (* x (* PI tau)))))
float code(float x, float tau) {
return (sinf((x * ((float) M_PI))) / (x * ((float) M_PI))) * (sinf(((x * ((float) M_PI)) * tau)) / (x * (((float) M_PI) * tau)));
}
function code(x, tau) return Float32(Float32(sin(Float32(x * Float32(pi))) / Float32(x * Float32(pi))) * Float32(sin(Float32(Float32(x * Float32(pi)) * tau)) / Float32(x * Float32(Float32(pi) * tau)))) end
function tmp = code(x, tau) tmp = (sin((x * single(pi))) / (x * single(pi))) * (sin(((x * single(pi)) * tau)) / (x * (single(pi) * tau))); end
\begin{array}{l}
\\
\frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \cdot \frac{\sin \left(\left(x \cdot \pi\right) \cdot tau\right)}{x \cdot \left(\pi \cdot tau\right)}
\end{array}
Initial program 98.0%
associate-*l*97.4%
associate-*l*98.0%
Simplified98.0%
Taylor expanded in x around inf 97.5%
Final simplification97.5%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* x (* PI tau)))) (* (/ (sin t_1) t_1) (/ (/ (sin (* x PI)) x) PI))))
float code(float x, float tau) {
float t_1 = x * (((float) M_PI) * tau);
return (sinf(t_1) / t_1) * ((sinf((x * ((float) M_PI))) / x) / ((float) M_PI));
}
function code(x, tau) t_1 = Float32(x * Float32(Float32(pi) * tau)) return Float32(Float32(sin(t_1) / t_1) * Float32(Float32(sin(Float32(x * Float32(pi))) / x) / Float32(pi))) end
function tmp = code(x, tau) t_1 = x * (single(pi) * tau); tmp = (sin(t_1) / t_1) * ((sin((x * single(pi))) / x) / single(pi)); end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := x \cdot \left(\pi \cdot tau\right)\\
\frac{\sin t_1}{t_1} \cdot \frac{\frac{\sin \left(x \cdot \pi\right)}{x}}{\pi}
\end{array}
\end{array}
Initial program 98.0%
expm1-log1p-u97.9%
Applied egg-rr97.9%
clear-num97.8%
expm1-log1p-u97.9%
inv-pow97.9%
Applied egg-rr97.9%
unpow-197.9%
clear-num98.0%
associate-/r*97.8%
Applied egg-rr97.8%
Taylor expanded in x around inf 97.8%
*-commutative97.8%
associate-*r*97.4%
*-commutative97.4%
*-commutative97.4%
associate-*r*97.9%
*-commutative97.9%
Simplified97.9%
Final simplification97.9%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* x (* PI tau)))) (* (/ (sin (* x PI)) (* x PI)) (/ (sin t_1) t_1))))
float code(float x, float tau) {
float t_1 = x * (((float) M_PI) * tau);
return (sinf((x * ((float) M_PI))) / (x * ((float) M_PI))) * (sinf(t_1) / t_1);
}
function code(x, tau) t_1 = Float32(x * Float32(Float32(pi) * tau)) return Float32(Float32(sin(Float32(x * Float32(pi))) / Float32(x * Float32(pi))) * Float32(sin(t_1) / t_1)) end
function tmp = code(x, tau) t_1 = x * (single(pi) * tau); tmp = (sin((x * single(pi))) / (x * single(pi))) * (sin(t_1) / t_1); end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := x \cdot \left(\pi \cdot tau\right)\\
\frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi} \cdot \frac{\sin t_1}{t_1}
\end{array}
\end{array}
Initial program 98.0%
associate-*l*97.4%
associate-*l*98.0%
Simplified98.0%
Final simplification98.0%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (* x PI) tau))) (* (/ (sin t_1) t_1) (/ (/ (* x PI) x) PI))))
float code(float x, float tau) {
float t_1 = (x * ((float) M_PI)) * tau;
return (sinf(t_1) / t_1) * (((x * ((float) M_PI)) / x) / ((float) M_PI));
}
function code(x, tau) t_1 = Float32(Float32(x * Float32(pi)) * tau) return Float32(Float32(sin(t_1) / t_1) * Float32(Float32(Float32(x * Float32(pi)) / x) / Float32(pi))) end
function tmp = code(x, tau) t_1 = (x * single(pi)) * tau; tmp = (sin(t_1) / t_1) * (((x * single(pi)) / x) / single(pi)); end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \left(x \cdot \pi\right) \cdot tau\\
\frac{\sin t_1}{t_1} \cdot \frac{\frac{x \cdot \pi}{x}}{\pi}
\end{array}
\end{array}
Initial program 98.0%
expm1-log1p-u97.9%
Applied egg-rr97.9%
clear-num97.8%
expm1-log1p-u97.9%
inv-pow97.9%
Applied egg-rr97.9%
unpow-197.9%
clear-num98.0%
associate-/r*97.8%
Applied egg-rr97.8%
Taylor expanded in x around 0 71.4%
Final simplification71.4%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (* x PI) tau))) (/ (sin t_1) t_1)))
float code(float x, float tau) {
float t_1 = (x * ((float) M_PI)) * tau;
return sinf(t_1) / t_1;
}
function code(x, tau) t_1 = Float32(Float32(x * Float32(pi)) * tau) return Float32(sin(t_1) / t_1) end
function tmp = code(x, tau) t_1 = (x * single(pi)) * tau; tmp = sin(t_1) / t_1; end
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \left(x \cdot \pi\right) \cdot tau\\
\frac{\sin t_1}{t_1}
\end{array}
\end{array}
Initial program 98.0%
expm1-log1p-u97.9%
Applied egg-rr97.9%
clear-num97.8%
expm1-log1p-u97.9%
inv-pow97.9%
Applied egg-rr97.9%
Taylor expanded in x around 0 71.4%
Final simplification71.4%
(FPCore (x tau) :precision binary32 (* (/ (sin (* x PI)) x) (/ 1.0 PI)))
float code(float x, float tau) {
return (sinf((x * ((float) M_PI))) / x) * (1.0f / ((float) M_PI));
}
function code(x, tau) return Float32(Float32(sin(Float32(x * Float32(pi))) / x) * Float32(Float32(1.0) / Float32(pi))) end
function tmp = code(x, tau) tmp = (sin((x * single(pi))) / x) * (single(1.0) / single(pi)); end
\begin{array}{l}
\\
\frac{\sin \left(x \cdot \pi\right)}{x} \cdot \frac{1}{\pi}
\end{array}
Initial program 98.0%
associate-*l*97.4%
associate-*l*98.0%
Simplified98.0%
Taylor expanded in x around 0 64.5%
associate-/r*64.6%
div-inv64.6%
Applied egg-rr64.6%
Final simplification64.6%
(FPCore (x tau) :precision binary32 (/ (sin (* x PI)) (* x PI)))
float code(float x, float tau) {
return sinf((x * ((float) M_PI))) / (x * ((float) M_PI));
}
function code(x, tau) return Float32(sin(Float32(x * Float32(pi))) / Float32(x * Float32(pi))) end
function tmp = code(x, tau) tmp = sin((x * single(pi))) / (x * single(pi)); end
\begin{array}{l}
\\
\frac{\sin \left(x \cdot \pi\right)}{x \cdot \pi}
\end{array}
Initial program 98.0%
associate-*l*97.4%
associate-*l*98.0%
Simplified98.0%
Taylor expanded in x around 0 64.5%
Final simplification64.5%
(FPCore (x tau) :precision binary32 (/ (/ (sin (* x PI)) x) PI))
float code(float x, float tau) {
return (sinf((x * ((float) M_PI))) / x) / ((float) M_PI);
}
function code(x, tau) return Float32(Float32(sin(Float32(x * Float32(pi))) / x) / Float32(pi)) end
function tmp = code(x, tau) tmp = (sin((x * single(pi))) / x) / single(pi); end
\begin{array}{l}
\\
\frac{\frac{\sin \left(x \cdot \pi\right)}{x}}{\pi}
\end{array}
Initial program 98.0%
associate-*l*97.4%
associate-*l*98.0%
Simplified98.0%
Taylor expanded in x around 0 64.5%
*-un-lft-identity64.5%
times-frac64.5%
Applied egg-rr64.5%
*-commutative64.5%
associate-*l/64.4%
div-inv64.6%
Applied egg-rr64.6%
Final simplification64.6%
(FPCore (x tau) :precision binary32 (/ (* x PI) (* x PI)))
float code(float x, float tau) {
return (x * ((float) M_PI)) / (x * ((float) M_PI));
}
function code(x, tau) return Float32(Float32(x * Float32(pi)) / Float32(x * Float32(pi))) end
function tmp = code(x, tau) tmp = (x * single(pi)) / (x * single(pi)); end
\begin{array}{l}
\\
\frac{x \cdot \pi}{x \cdot \pi}
\end{array}
Initial program 98.0%
associate-*l*97.4%
associate-*l*98.0%
Simplified98.0%
Taylor expanded in x around 0 64.5%
Taylor expanded in x around 0 63.8%
Final simplification63.8%
(FPCore (x tau) :precision binary32 (* x (/ 1.0 x)))
float code(float x, float tau) {
return x * (1.0f / x);
}
real(4) function code(x, tau)
real(4), intent (in) :: x
real(4), intent (in) :: tau
code = x * (1.0e0 / x)
end function
function code(x, tau) return Float32(x * Float32(Float32(1.0) / x)) end
function tmp = code(x, tau) tmp = x * (single(1.0) / x); end
\begin{array}{l}
\\
x \cdot \frac{1}{x}
\end{array}
Initial program 98.0%
associate-*l*97.4%
associate-*l*98.0%
Simplified98.0%
Taylor expanded in x around 0 64.5%
*-un-lft-identity64.5%
times-frac64.5%
Applied egg-rr64.5%
Taylor expanded in x around 0 63.8%
Final simplification63.8%
herbie shell --seed 2024024
(FPCore (x tau)
:name "Lanczos kernel"
:precision binary32
:pre (and (and (<= 1e-5 x) (<= x 1.0)) (and (<= 1.0 tau) (<= tau 5.0)))
(* (/ (sin (* (* x PI) tau)) (* (* x PI) tau)) (/ (sin (* x PI)) (* x PI))))