demo D199

Statistics of a selection in htmx

Drag a rectangle; it is summarised as one set of figures

grid.selection.statistics()

This grid summarises a dragged rectangle of cells as one set of figures. It answers 'what do these add up to' for an ad-hoc block, so a reader checks a subtotal by selecting it, the way a spreadsheet status bar does.

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@1.107.0/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="selection-statistics-table" data-lattice-grid>
  <thead>
    <tr>
      <th data-field="symbol">Symbol</th>
      <th data-field="desk">Desk</th>
      <th data-field="price">Price</th>
      <th data-field="bid">Bid</th>
      <th data-field="volume">Volume</th>
      <th data-field="notional">Notional</th>
    </tr>
  </thead>
  <tbody>
    <tr data-id="INS-0000000"><td>ELMW.G0</td><td>Rates</td><td>462.0258</td><td>461.2688</td><td>239420</td><td>110618217</td></tr>
    <tr data-id="INS-0000001"><td>RVNS.A1</td><td>Credit</td><td>241.8711</td><td>241.7978</td><td>119353</td><td>28868041</td></tr>
    <tr data-id="INS-0000002"><td>NRTH.E2</td><td>Commodities</td><td>98.9614</td><td>98.8353</td><td>160242</td><td>15857773</td></tr>
    <!-- the rest of the rows, rendered by your server -->
  </tbody>
</table>
<div id="out" style="margin-top: 12px; font-family: monospace">Select a block of numeric cells</div>

<script type="module">
  import { hydrateTable } from 'https://cdn.latticegrid.dev/lattice-grid@1.107.0/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('selection-statistics-table'), {
    selection: { mode: 'multiple', ranges: true },
    columns: [
      { field: 'symbol', title: 'Symbol', layout: { pin: 'start', width: 120 } },
      { field: 'desk', title: 'Desk', filter: { type: 'set' } },
      { field: 'price', title: 'Price', type: 'number' },
      { field: 'bid', title: 'Bid', type: 'number' },
      { field: 'volume', title: 'Volume', type: 'number' },
      { field: 'notional', title: 'Notional', type: 'number',
        format: { style: 'currency', currency: 'USD' }, total: 'sum' },
    ],
  });

  // Drag a block of numeric cells and read its shape back at once: how many
  // cells, the median, the quartiles and the spread of the selected values.
  const out = document.getElementById('out');
  grid.on('range:changed', () => {
    const s = grid.selection.statistics();
    out.textContent = s
      ? s.cells + ' cells, median ' + s.median + ', q1 ' + s.q1 + ', q3 ' + s.q3 + ', sd ' + s.stddev
      : 'Select a block of numeric cells';
  });
</script>