biojs-io-graduates/lib/index.js

A parser for the BioJS tutorial graduate list

/*
* Welcome to the biojs tutorial. 
* Can you build a parser for counting the number of appearances for each country in the data set?
* URL to this tutorial: http://edu.biojs.net/graduates/basic_io/
*/

var _ = require("lodash"); // only needed for a shorter way to use parse
var parser = require("biojs-io-parser"); // adds extra methods like read

var graduates = {};

parser.mixin(graduates); // graduates inherits the methods from the generic io parser

graduates.read_static = function() {
  var data = "greenify:DE\ndaviddao:HK\nmhelvens:NL\ntimruffles:UK\niriscshih:TW\n\n";
  return graduates.parse(data);
};

graduates.parse = function(data) {
  return _(data.split("\n")).map(function(e) {
    return e.split(":");
  }).filter(function(e) {
    return e.length === 2;
  }).map(function(e) {
    return e[1];
  }).countBy().value();
};

graduates.parse_long = function(data) {
  // count countries
  var parsed = {};
  for (var i = 0; i < data.length; i++) {
    // skip empty rows
    if (data[i].trim().length === 0) {
      continue;
    }
    var row = data[i].split(":");
    // init if new
    if (typeof parsed[row[1]] === "undefined") {
      parsed[row[1]] = 0;
    }
    parsed[row[1]] ++;
  }
  return parsed;
};

module.exports = graduates;