For Better names in Chance.jshttp://chancejs.com/#todo

names.js

/*
 * For http://chancejs.com/#todo - Better names
 * Get national data from http://www.ssa.gov/oact/babynames/limits.html
 * extract names.zip
 * cat yob*.txt > all.csv
 */

var fs = require('fs');

var filename = 'all.csv', males = {}, females = {};

fs.readFile(filename, {encoding: 'utf-8'}, function (err, data) {
  if (err) throw err;
  data.split('\n').forEach(function(line) {
    var parts = line.split(',');
    if ( parts[1] == 'M' ) {
      males[parts[0]] = (males[parts[0]] || 0) + parseInt(parts[2]);
    } else {
      females[parts[0]] = (females[parts[0]] || 0) + parseInt(parts[2]);
    }
  });
  var desc = function(a,b) {
    return b[1] - a[1];
  },
  name = function(x) {
    return x[0];
  },
  notEmpty = function(x) {
    return x.length > 0;
  },
  maleArr = Object.keys(males).map(function(name) {
    return [name, males[name]];
  }).sort(desc).map(name).filter(notEmpty).slice(0, 250),
  femaleArr = Object.keys(females).map(function(name) {
    return [name, females[name]];
  }).sort(desc).map(name).filter(notEmpty).slice(0, 250);
  var outFile = 'chance-names.js';
  fs.writeFile(
    outFile,
    'var firstNames = ' + JSON.stringify({Male: maleArr, Female: femaleArr}) + ';',
    function(err) {
      if ( err ) throw err;
      console.log('wrote %s successfully', outFile);
    });
});