JavaScript and Open Data

Introduction to Part 3

Let us talk about “Big Data”: not about a Big Bang or a Big Brother myth, but merely about a big reservoir of data, of any kind, which we can examine under two facets:

• – we can consider the Big facet, when billions of data concern a particular topics, which we can process through distributed statistical processing or deep learning.
• – we can consider the Data facet, meaning that we can gather information pieces about almost anything, without being constrained by performance issues.

Our approach focuses rather on that second facet, in particular on the servers that deliver data that can be accessed through APIs, or JSONP, or even plain text files such as CSV data, or loosely structured data such as RSS feeds.

Being able to process such data requires different skills:

• – accessing several resources: monitoring AJAX requests and responses;
• – aggregating data, joining data (SQL like GroupBy and Join);
• – displaying graphs, plotting curves, animating;
• – mapping data on cartographic sources, map-data interactions.

The first application works on temporal data series. We will put in practice the AJAX technology, the array methods, the canvas graphic tools and animation tools.

The second application deals with multiple tabulated data sources in relational or hierarchical mode. We will present an operation similar to GroupBy and Join; we will face string comparison issues and use the prototypal background of JavaScript for a smooth integration of JSON data. Performance ...