
(FPCore (x tau) :precision binary32 (let* ((t_1 (* x (PI))) (t_2 (* t_1 tau))) (* (/ (sin t_2) t_2) (/ (sin t_1) t_1))))
\begin{array}{l}
\\
\begin{array}{l}
t_1 := x \cdot \mathsf{PI}\left(\right)\\
t_2 := t\_1 \cdot tau\\
\frac{\sin t\_2}{t\_2} \cdot \frac{\sin t\_1}{t\_1}
\end{array}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 14 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x tau) :precision binary32 (let* ((t_1 (* x (PI))) (t_2 (* t_1 tau))) (* (/ (sin t_2) t_2) (/ (sin t_1) t_1))))
\begin{array}{l}
\\
\begin{array}{l}
t_1 := x \cdot \mathsf{PI}\left(\right)\\
t_2 := t\_1 \cdot tau\\
\frac{\sin t\_2}{t\_2} \cdot \frac{\sin t\_1}{t\_1}
\end{array}
\end{array}
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (PI) x)) (t_2 (* t_1 tau))) (* (/ (sin t_1) t_1) (/ (sin t_2) t_2))))
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \mathsf{PI}\left(\right) \cdot x\\
t_2 := t\_1 \cdot tau\\
\frac{\sin t\_1}{t\_1} \cdot \frac{\sin t\_2}{t\_2}
\end{array}
\end{array}
Initial program 97.7%
Final simplification97.7%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (* tau (PI)) x)) (t_2 (* (PI) x))) (* (/ (sin t_1) t_2) (/ (sin t_2) t_1))))
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \left(tau \cdot \mathsf{PI}\left(\right)\right) \cdot x\\
t_2 := \mathsf{PI}\left(\right) \cdot x\\
\frac{\sin t\_1}{t\_2} \cdot \frac{\sin t\_2}{t\_1}
\end{array}
\end{array}
Initial program 97.7%
lift-*.f32N/A
lift-/.f32N/A
clear-numN/A
un-div-invN/A
frac-2negN/A
associate-/r/N/A
lower-*.f32N/A
Applied rewrites97.5%
lift-/.f32N/A
lift-/.f32N/A
associate-/l/N/A
lift-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lift-*.f32N/A
*-commutativeN/A
lift-*.f32N/A
associate-/r*N/A
Applied rewrites97.5%
Applied rewrites97.3%
Final simplification97.3%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (PI) x))) (* (/ (sin t_1) (* tau x)) (/ (sin (* t_1 tau)) (* t_1 (PI))))))
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \mathsf{PI}\left(\right) \cdot x\\
\frac{\sin t\_1}{tau \cdot x} \cdot \frac{\sin \left(t\_1 \cdot tau\right)}{t\_1 \cdot \mathsf{PI}\left(\right)}
\end{array}
\end{array}
Initial program 97.7%
Taylor expanded in x around inf
associate-/r*N/A
unpow2N/A
unpow2N/A
unswap-sqrN/A
associate-/r*N/A
*-commutativeN/A
associate-/l/N/A
times-fracN/A
times-fracN/A
lower-*.f32N/A
Applied rewrites96.9%
Final simplification96.9%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (PI) x))) (/ (* (sin (* (* tau (PI)) x)) (sin t_1)) (* (* t_1 tau) t_1))))
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \mathsf{PI}\left(\right) \cdot x\\
\frac{\sin \left(\left(tau \cdot \mathsf{PI}\left(\right)\right) \cdot x\right) \cdot \sin t\_1}{\left(t\_1 \cdot tau\right) \cdot t\_1}
\end{array}
\end{array}
Initial program 97.7%
lift-*.f32N/A
lift-/.f32N/A
clear-numN/A
un-div-invN/A
frac-2negN/A
associate-/r/N/A
lower-*.f32N/A
Applied rewrites97.5%
lift-/.f32N/A
lift-/.f32N/A
associate-/l/N/A
lift-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lift-*.f32N/A
*-commutativeN/A
lift-*.f32N/A
associate-/r*N/A
Applied rewrites97.5%
lift-*.f32N/A
lift-/.f32N/A
lift-/.f32N/A
associate-/l/N/A
associate-*l/N/A
frac-timesN/A
frac-2negN/A
lift-*.f32N/A
associate-/r*N/A
Applied rewrites96.9%
Final simplification96.9%
(FPCore (x tau) :precision binary32 (/ (* (sin (* (* tau (PI)) x)) (sin (* (PI) x))) (* (* x x) (* (* (PI) (PI)) tau))))
\begin{array}{l}
\\
\frac{\sin \left(\left(tau \cdot \mathsf{PI}\left(\right)\right) \cdot x\right) \cdot \sin \left(\mathsf{PI}\left(\right) \cdot x\right)}{\left(x \cdot x\right) \cdot \left(\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot tau\right)}
\end{array}
Initial program 97.7%
lift-*.f32N/A
lift-/.f32N/A
clear-numN/A
un-div-invN/A
frac-2negN/A
associate-/r/N/A
lower-*.f32N/A
Applied rewrites97.5%
lift-/.f32N/A
lift-/.f32N/A
associate-/l/N/A
lift-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lift-*.f32N/A
*-commutativeN/A
lift-*.f32N/A
associate-/r*N/A
Applied rewrites97.5%
Applied rewrites96.7%
Final simplification96.7%
(FPCore (x tau) :precision binary32 (* (sin (* (* tau (PI)) x)) (/ (sin (* (PI) x)) (* (* (* (* x x) (PI)) (PI)) tau))))
\begin{array}{l}
\\
\sin \left(\left(tau \cdot \mathsf{PI}\left(\right)\right) \cdot x\right) \cdot \frac{\sin \left(\mathsf{PI}\left(\right) \cdot x\right)}{\left(\left(\left(x \cdot x\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \mathsf{PI}\left(\right)\right) \cdot tau}
\end{array}
Initial program 97.7%
lift-*.f32N/A
lift-/.f32N/A
clear-numN/A
un-div-invN/A
frac-2negN/A
associate-/r/N/A
lower-*.f32N/A
Applied rewrites97.5%
Applied rewrites97.5%
Taylor expanded in x around inf
lower-/.f32N/A
lower-sin.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f32N/A
*-commutativeN/A
lower-*.f32N/A
unpow2N/A
associate-*r*N/A
lower-*.f32N/A
lower-*.f32N/A
unpow2N/A
lower-*.f32N/A
lower-PI.f32N/A
lower-PI.f3296.6
Applied rewrites96.6%
Final simplification96.6%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (PI) x)) (t_2 (* t_1 tau))) (* (/ (/ (sin t_2) t_2) t_1) t_1)))
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \mathsf{PI}\left(\right) \cdot x\\
t_2 := t\_1 \cdot tau\\
\frac{\frac{\sin t\_2}{t\_2}}{t\_1} \cdot t\_1
\end{array}
\end{array}
Initial program 97.7%
lift-*.f32N/A
lift-/.f32N/A
clear-numN/A
un-div-invN/A
frac-2negN/A
associate-/r/N/A
lower-*.f32N/A
Applied rewrites97.5%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3268.5
Applied rewrites68.5%
Final simplification68.5%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (PI) x)) (t_2 (* (* tau (PI)) x))) (* (/ (/ t_1 t_1) t_2) (sin t_2))))
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \mathsf{PI}\left(\right) \cdot x\\
t_2 := \left(tau \cdot \mathsf{PI}\left(\right)\right) \cdot x\\
\frac{\frac{t\_1}{t\_1}}{t\_2} \cdot \sin t\_2
\end{array}
\end{array}
Initial program 97.7%
lift-*.f32N/A
lift-/.f32N/A
clear-numN/A
un-div-invN/A
frac-2negN/A
associate-/r/N/A
lower-*.f32N/A
Applied rewrites97.5%
Applied rewrites97.5%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3268.4
Applied rewrites68.4%
Final simplification68.4%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (PI) x))) (/ (* (/ 1.0 tau) (sin (* t_1 tau))) t_1)))
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \mathsf{PI}\left(\right) \cdot x\\
\frac{\frac{1}{tau} \cdot \sin \left(t\_1 \cdot tau\right)}{t\_1}
\end{array}
\end{array}
Initial program 97.7%
lift-*.f32N/A
lift-/.f32N/A
associate-*r/N/A
lower-/.f32N/A
Applied rewrites97.5%
Taylor expanded in x around 0
lower-/.f3268.3
Applied rewrites68.3%
Final simplification68.3%
(FPCore (x tau) :precision binary32 (* (/ 1.0 (* (* (PI) x) tau)) (sin (* (* tau (PI)) x))))
\begin{array}{l}
\\
\frac{1}{\left(\mathsf{PI}\left(\right) \cdot x\right) \cdot tau} \cdot \sin \left(\left(tau \cdot \mathsf{PI}\left(\right)\right) \cdot x\right)
\end{array}
Initial program 97.7%
lift-*.f32N/A
lift-/.f32N/A
clear-numN/A
un-div-invN/A
frac-2negN/A
associate-/r/N/A
lower-*.f32N/A
Applied rewrites97.5%
Applied rewrites97.5%
Taylor expanded in x around 0
lower-/.f32N/A
*-commutativeN/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3268.2
Applied rewrites68.2%
Final simplification68.2%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (PI) x))) (/ (* (sin t_1) tau) (* t_1 tau))))
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \mathsf{PI}\left(\right) \cdot x\\
\frac{\sin t\_1 \cdot tau}{t\_1 \cdot tau}
\end{array}
\end{array}
Initial program 97.7%
lift-*.f32N/A
lift-/.f32N/A
associate-*l/N/A
lower-/.f32N/A
Applied rewrites97.5%
Taylor expanded in tau around 0
*-commutativeN/A
lower-*.f32N/A
lower-sin.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3261.2
Applied rewrites61.2%
Final simplification61.2%
(FPCore (x tau) :precision binary32 (let* ((t_1 (* (PI) x))) (* (- (sin t_1)) (/ -1.0 t_1))))
\begin{array}{l}
\\
\begin{array}{l}
t_1 := \mathsf{PI}\left(\right) \cdot x\\
\left(-\sin t\_1\right) \cdot \frac{-1}{t\_1}
\end{array}
\end{array}
Initial program 97.7%
lift-*.f32N/A
lift-/.f32N/A
clear-numN/A
un-div-invN/A
frac-2negN/A
associate-/r/N/A
lower-*.f32N/A
Applied rewrites97.5%
Taylor expanded in x around 0
lower-/.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3261.2
Applied rewrites61.2%
Final simplification61.2%
(FPCore (x tau) :precision binary32 (+ 1.0 (* (* -0.16666666666666666 (* (PI) (PI))) (* x x))))
\begin{array}{l}
\\
1 + \left(-0.16666666666666666 \cdot \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \left(x \cdot x\right)
\end{array}
Initial program 97.7%
Taylor expanded in x around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f32N/A
Applied rewrites60.3%
Taylor expanded in tau around 0
Applied rewrites59.8%
Applied rewrites61.1%
Final simplification61.1%
(FPCore (x tau) :precision binary32 1.0)
float code(float x, float tau) {
return 1.0f;
}
real(4) function code(x, tau)
real(4), intent (in) :: x
real(4), intent (in) :: tau
code = 1.0e0
end function
function code(x, tau) return Float32(1.0) end
function tmp = code(x, tau) tmp = single(1.0); end
\begin{array}{l}
\\
1
\end{array}
Initial program 97.7%
Taylor expanded in x around 0
Applied rewrites60.4%
herbie shell --seed 2024295
(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)))))