exclusiveScan - nodef/extra-array GitHub Wiki

Perform exclusive prefix scan from left to right.

Alternatives: exclusiveScan, exclusiveScan$. Similar: inclusiveScan, exclusiveScan.

function exclusiveScan(x, fr, acc)
// x:   an array
// fr:  reduce function (acc, v, i, x)
// acc: initial value

const xarray = require('extra-array');

var x = [1, 2, 3, 4, 5];
var y = xarray.exclusiveScan(x, (acc, v) => acc+v, 0);
// → [ 0, 1, 3, 6, 10 ]

var y = xarray.exclusiveScan(x, (acc, v) => acc+v, 10);
// → [ 10, 11, 13, 16, 20 ]

References