plotly.js/src/traces/histogram2d/hover.js

The open source javascript graphing library that powers plotly

'use strict';

var heatmapHover = require('../heatmap/hover');
var hoverLabelText = require('../../plots/cartesian/axes').hoverLabelText;

module.exports = function hoverPoints(pointData, xval, yval, hovermode, opts) {
    var pts = heatmapHover(pointData, xval, yval, hovermode, opts);

    if(!pts) return;

    pointData = pts[0];
    var indices = pointData.index;
    var ny = indices[0];
    var nx = indices[1];
    var cd0 = pointData.cd[0];
    var trace = cd0.trace;
    var xRange = cd0.xRanges[nx];
    var yRange = cd0.yRanges[ny];

    pointData.xLabel = hoverLabelText(pointData.xa, [xRange[0], xRange[1]], trace.xhoverformat);
    pointData.yLabel = hoverLabelText(pointData.ya, [yRange[0], yRange[1]], trace.yhoverformat);

    return pts;
};