Band-limited step function
code:latex
{\rm BLEP}(t)
= \int_{-\infty}^{t} {\rm sinc}(\tau) \ d\tau
= \frac{1}{2} + \frac{1}{\pi} \ {\rm Si} (\pi t)
ここで、$ {\rm Si}(x) = \int_0^x \frac{\sin u}{u} \ duは正弦積分 以下のPaperが初出?
Desmos
https://gyazo.com/40158f8b8a65c562c9a82e9eecb41d86