demo D189

Quantile colour scales in htmx

A scale that ignores the outlier flattening it

scale: { from: 'quantile' }

This grid shades a column by quantile rather than by raw range, so one extreme value does not flatten the colour for everything else. It keeps a heat map readable when the data is skewed, spreading colour by rank so the middle of the distribution still shows contrast.

Building…

Loading a live grid…

This is the htmx version. A server-rendered table is upgraded in place, so the page is readable before any script runs and gains the full grid when the module loads, which suits a progressively enhanced app.

The configuration

<link rel="stylesheet" href="https://cdn.latticegrid.dev/lattice-grid@1.108.0/lattice-grid.min.css">

<!-- A real, server-rendered table: readable with JavaScript off. data-field on
     each header names the column that cell becomes, and data-id on each row is
     the key the grid carries it under. -->
<table id="quantile-colour-scales-table" data-lattice-grid>
  <thead>
    <tr>
      <th data-field="node">Node</th>
      <th data-field="value">min-max scale</th>
    </tr>
  </thead>
  <tbody>
    <tr data-id="1"><td>node-001</td><td>3000</td></tr>
    <tr data-id="2"><td>node-002</td><td>52</td></tr>
    <tr data-id="3"><td>node-003</td><td>89</td></tr>
    <!-- the rest of the rows, rendered by your server -->
  </tbody>
</table>

<script type="module">
  import { hydrateTable } from 'https://cdn.latticegrid.dev/lattice-grid@1.108.0/modules/htmx.esm.min.js';

  // The markup carries the rows; a server-rendered table's column types are
  // declared in the config hydrateTable takes. The grid replaces the table
  // where it stood.
  const grid = hydrateTable(document.getElementById('quantile-colour-scales-table'), {
    // The same skewed column, two scales. A min-max scale is flattened by one
    // large value; a quantile scale spans the 5th to 95th percentile instead.
    formatting: {
      'v-minmax':   [{ scale: { from: 'minmax', colours: ['#f5f7fa', '#1a6bc7'] } }],
      'v-quantile': [{ scale: { from: 'quantile', low: 5, high: 95, colours: ['#f5f7fa', '#1a6bc7'] } }],
    },
    columns: [
      { field: 'node', title: 'Node', layout: { pin: 'start', width: 150 } },
      { field: 'value', id: 'v-minmax', title: 'min-max scale', type: 'number' },
      { field: 'value', id: 'v-quantile', title: 'quantile scale', type: 'number' },
      { field: 'value', title: 'value', type: 'number' },
    ],
  });
</script>