Estimates new values between existing ones.
Similar: interleave, intermix, interpolate, intersperse.
This is part of package extra-array.
array.interpolate(x, fc);
// x: an array
// fc: combine function (a, b)
const array = require("extra-array");
var x = [1, 2, 3];
array.interpolate(x, (a, b) => (a + b)/2);
// [ 1, 1.5, 2, 2.5, 3 ]