xsheetjs/demos/array/linest.js

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/* xlsx.js (C) 2013-present SheetJS -- http://sheetjs.com */
/*global module, require, XLSX:true */
if(typeof require !== 'undefined' && typeof XLSX === 'undefined') XLSX = require('xlsx');
function generate_random_file(n) {
if(!n) n = 100;
var aoo = [];
var x_ = 0, y_ = 0, xx = 0, xy = 0;
for(var i = 0; i < n; ++i) {
var y = Math.fround(2 * i + Math.random());
aoo.push({x:i, y:y});
x_ += i / n; y_ += y / n; xx += i*i; xy += i * y;
}
var m = Math.fround((xy - n * x_ * y_)/(xx - n * x_ * x_));
console.log(m, Math.fround(y_ - m * x_), "JS Pre");
var ws = XLSX.utils.json_to_sheet(aoo);
var wb = XLSX.utils.book_new();
XLSX.utils.book_append_sheet(wb, ws, "Sheet1");
ws = XLSX.utils.aoa_to_sheet([[2, 0]]);
XLSX.utils.sheet_set_array_formula(ws, "A1:B1", "LINEST(Sheet1!B2:B101,Sheet1!A2:A101)");
XLSX.utils.book_append_sheet(wb, ws, "Sheet2");
XLSX.writeFile(wb, "linreg.xlsx");
}
if(typeof module !== 'undefined') module.exports = {
generate_random_file: generate_random_file
};