liveBook · Manning

Data measurement

As explained in D3.js in Action, Third Edition

Data measurement is the examination and quantification of dataset characteristics to understand its contents and range.

Data measurement examines a complete dataset before visualization, revealing its size, range, and notable values. In D3, perform it after loading and formatting data through a Promise. section 3.2.3

Measuring survey technologies

After d3.csv() transforms each row into an object, the fulfilled Promise exposes the complete array. A survey dataset contains 33 technologies, with counts ranging from 20 to 1,078; sorting by count prepares the data for a bar chart. section 3.2.3

How D3.js in Action, Third Edition covers it

How deep it goes
Explains Promise-based access, array inspection, range functions, and sorting, but stops short of visualization construction.
Examples
Uses a 33-item technology survey, count range 20–1,078, console logging, and descending record sorting.
What it assumes
Assumes basic JavaScript arrays and callbacks while teaching dataset access through d3.csv(), row conversion, and Promise callbacks.
What you can do after
Apply it via D3 to inspect, summarize, and order loaded records before building a chart.
How it connects
Connects JavaScript Promises, CSV parsing, data transformation, data visualization, arrays, and sorting.
Cover of D3.js in Action, Third Edition
liveBookmanning.com
Read D3.js in Action, Third Edition on liveBook Get the book at manning.com

This explainer was generated by Manning's knowledge graph from the text of D3.js in Action, Third Edition. The section links point to the parts of the book it draws on.