d3.scale.linear() vs d3.scaleLinear()

Question

Hi I'm looking at the documentation for scales and it shows a format like this var x = d3.scaleLinear([10,130]).range([0,960]) I feel like this is strange because most examples that I see online use something like this:

var x = d3.scale.linear().domain([10,130]).range([0,960]) and it works.

If I use var x = d3.scaleLinear([10,130]).range([0,960]); I get an error like

TypeError: d3.scaleLinear is not a function

Why do you think there is a discrepancy between the examples in the documentation and what I see in examples online? maybe I don't understand how to read documentation.

EDIT : This is the current documentation for scales.

Answer 1

To create a linear scale with d3.js version 3 use API d3.scale.linear()

and to create a linear scale with version 4 and 5 use API d3.scaleLinear()

API references for creating a linear scale for both the versions can be found here:

v3.x scale.linear

v4.x scaleLinear

Answer 2

As specified by Hina, d3.scale.linear() is used on D3 3.0, and d3 4.0 adopted the flat namespace convention. Here is a snippet from the d3 changelog summary

If you don’t care about modularity, you can mostly ignore this change and keep using the default bundle. However, there is one unavoidable consequence of adopting ES6 modules: every symbol in D3 4.0 now shares a flat namespace rather than the nested one of D3 3.x. For example, d3.scale.linear is now d3.scaleLinear,...

Source: https://github.com/d3/d3/blob/master/CHANGES.md

EDIT: Forgot to mention - to fix your error, you may have to update the link or file to d3 that you have in your program. I call it directly from the website with:

<script src="https://d3js.org/d3.v4.min.js"></script>

Answer 3

The documentation you're looking at is for a plugin for D3 -- how to install it is described further down on that same page. It will eventually be part of the next major release of D3.

Answer 4

They are doing exactly the same thing, but it's just code change happen to D3.js from version 3 to version 4...

So linear is not property of scale object of d3 framework anymore...

instead it's part of d3 with camelCase syntax...

So d3.js v3 use d3.scale.linear()

and to create a linear scale with v4 use d3.scaleLinear() instead...

version 3:

d3.scale.linear()

Constructs a new linear scale with the default domain [0,1] and the default range [0,1]. Thus, the default linear scale is equivalent to the identity function for numbers; for example linear(0.5) returns 0.5.

version 4:

d3.scaleLinear()

Constructs a new continuous scale with the unit domain [0, 1], the unit range [0, 1], the default interpolator and clamping disabled. Linear scales are a good default choice for continuous quantitative data because they preserve proportional differences. Each range value y can be expressed as a function of the domain value x: y = mx + b.