javascript - Finding an unknown value between 2 data points -

javascript - Finding an unknown value between 2 data points -

basically have set of info like

var info = [ {idx: 0, value: 10}, {idx: 20, value: 15}, {idx: 45, value: 24}, {idx: 100, value: 55}, ];

i'm looking way interpolate/estimate value of unmapped point (such idx of 32) be. i'm little out of element here, , love larn more how tackle problem, direction appreciated!

javascript math