D3.js using ordinal scale on a linear scale

Question

Why is it better to use this instead of a linear scale to create an ordered chat? The argument I heard is that this can lead to an ordering of the data sets, but could it not be done if you set the index number of the individual data as the x coordinate?

dataset = [ 5, 10, 13, 19, 21, 25, 22, 18, 15, 13];

var xScale = d3.scale.ordinal()
    .domain(d3.range(dataset.length))

Answer 1

The reason you should use ordinal scale instead of linear scale is simple, although many people are wrong:

Bar charts, by their very nature, consist of columns representing a categorical variable. . , , , . " ", : , , , . - .. , , , .

, :

dataset = [5, 10, 13, 19, 21, 25, 22, 18, 15, 13];

5, 10 . (, "10 5" ), .

, , ( " " ):

var w = 300,
  h = 200,
  padding = 20;
var svg = d3.select("body")
  .append("svg")
  .attr("width", w)
  .attr("height", h);

dataset = [5, 10, 13, 19, 21, 25, 22, 18, 15, 13];

var xScale = d3.scaleBand()
  .range([30, w])
  .domain(d3.range(dataset.length))
  .padding(0.2);

var yScale = d3.scaleLinear()
  .range([h - padding, padding])
  .domain([0, d3.max(dataset)]);

var bars = svg.selectAll("foo")
  .data(dataset)
  .enter()
  .append("rect")
  .attr("x", (d, i) => xScale(i))
  .attr("width", xScale.bandwidth())
  .attr("height", d => h - padding - yScale(d))
  .attr("y", d => yScale(d))
  .attr("fill", "teal");

var gX = svg.append("g")
  .attr("transform", "translate(0," + (h - padding) + ")")
  .call(d3.axisBottom(xScale));
  
var gY = svg.append("g")
  .attr("transform", "translate(30,0)")
  .call(d3.axisLeft(yScale));

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

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0 9 . : : . 0, 1, 2... ( , ) , ( 4 2 2). , "A", "B", "C" .. .

, , , . , . , : , .

var w = 300,
  h = 200,
  padding = 20;
var svg = d3.select("body")
  .append("svg")
  .attr("width", w)
  .attr("height", h);

dataset = [5, 10, 13, 19, 21, 25, 22, 18, 15, 13];

var data = [];

dataset.forEach((d,i)=>data.push({index: i, value:d}));

data.sort((a,b)=>d3.descending(a.value, b.value));

var xScale = d3.scaleBand()
  .range([30, w])
  .domain(data.map(d=>d.index))
  .padding(0.2);

var yScale = d3.scaleLinear()
  .range([h - padding, padding])
  .domain([0, d3.max(data, d=>d.value)]);

var bars = svg.selectAll("foo")
  .data(data)
  .enter()
  .append("rect")
  .attr("x", (d) => xScale(d.index))
  .attr("width", xScale.bandwidth())
  .attr("height", d => h - padding - yScale(d.value))
  .attr("y", d => yScale(d.value))
  .attr("fill", "teal");

var gX = svg.append("g")
  .attr("transform", "translate(0," + (h - padding) + ")")
  .call(d3.axisBottom(xScale));
  
var gY = svg.append("g")
  .attr("transform", "translate(30,0)")
  .call(d3.axisLeft(yScale));

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

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