Source: cirosantilli/flat-top-bump-function
= Flat top bump function
https://math.stackexchange.com/questions/1786964/is-it-possible-to-construct-a-smooth-flat-top-bump-function
= Flat top bump function
https://math.stackexchange.com/questions/1786964/is-it-possible-to-construct-a-smooth-flat-top-bump-function