Initial

.github/workflows/gh-pages-deploy.yml

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+name: GitHub Pages
+
+on:
+  push:
+    branches: [master]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Use Node.js 16.x
+        uses: actions/setup-node@v1
+        with:
+          node-version: "16.x"
+
+      - name: Build
+        env:
+          LCJS_LICENSE: ${{ secrets.LCJS_DEPLOY_LICENSE }}
+        run: |
+          npm install
+          npm run build
+
+      - name: Deploy
+        uses: peaceiris/actions-gh-pages@v3
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: ./dist
+          publish_branch: gh-pages

.gitignore

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+node_modules
+dist

LICENSE

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+MIT License
+
+Copyright (c) 2022 LightningChart Ltd.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

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+# JavaScript Histogram of Gaussian Distribution.
+
+![JavaScript Histogram of Gaussian Distribution.](histogramGaussian-darkGold.png)
+
+This demo application belongs to the set of examples for LightningChart JS, data visualization library for JavaScript.
+
+LightningChart JS is entirely GPU accelerated and performance optimized charting library for presenting massive amounts of data. It offers an easy way of creating sophisticated and interactive charts and adding them to your website or web application.
+
+The demo can be used as an example or a seed project. Local execution requires the following steps:
+
+-   Make sure that relevant version of [Node.js](https://nodejs.org/en/download/) is installed
+-   Open the project folder in a terminal:
+
+          npm install              # fetches dependencies
+          npm start                # builds an application and starts the development server
+
+-   The application is available at _http://localhost:8080_ in your browser, webpack-dev-server provides hot reload functionality.
+
+
+## Description
+
+Example showcasing LightningChart Histogram visualization using Bar Chart.
+
+Bar Chart can be used as a histogram by calculating the bins manually using the following function:
+
+```js
+const calculateHistogramBins = (data, numberOfBins) => {
+    const minValue = Math.min(...data)
+    const maxValue = Math.max(...data)
+    const binSize = (maxValue - minValue) / numberOfBins
+
+    // Calculate bin intervals
+    const bins = []
+    for (let i = 0; i < numberOfBins; i++) {
+        const binStart = minValue + i * binSize
+        const binEnd = minValue + (i + 1) * binSize
+        bins.push({
+            binStart: parseFloat(binStart.toFixed(2)),
+            binEnd: parseFloat(binEnd.toFixed(2)),
+            values: Array(),
+        })
+    }
+    bins[numberOfBins - 1].binEnd = maxValue
+
+    // Map data to bins
+    data.forEach((value) => {
+        const binIndex = Math.floor((value - minValue) / binSize)
+        if (binIndex >= 0 && binIndex < numberOfBins) {
+            bins[binIndex].values.push(value)
+        }
+    })
+
+    // Create input data for bar chart
+    const barChartData = []
+    bins.forEach((interval) => {
+        barChartData.push({
+            category: `${(interval.binStart + (interval.binStart === minValue ? 0 : 0.01)).toFixed(2)}—${
+                interval.binEnd < 0 ? `(${interval.binEnd.toFixed(2)})` : interval.binEnd.toFixed(2)
+            }`,
+            value: interval.values.length,
+        })
+    })
+    return barChartData
+}
+```
+
+In this example, a normally distributed dataset is generated by the [Box–Muller transform method](https://en.wikipedia.org/wiki/Box%E2%80%93Muller_transform):
+
+```js
+const generateGaussianRandom = (length) => {
+    const samples = []
+    for (let i = 0; i < length; i++) {
+        let u = 0,
+            v = 0,
+            s = 0
+        while (s === 0 || s >= 1) {
+            u = Math.random() * 2 - 1
+            v = Math.random() * 2 - 1
+            s = u * u + v * v
+        }
+        const temp = Math.sqrt((-2 * Math.log(s)) / s)
+        const sample = u * temp
+        samples.push(sample)
+    }
+    return samples
+}
+```
+
+In order to preserve the bell curve shape, automatic sorting has to be turned off by `barChart.setSorting(BarChartSorting.Disabled)`
+
+The number of histogram bins can be changed dynamically by the user using the HTML number input. The chart updates automatically from these interactions.
+
+
+## API Links
+
+* [Bar Chart]
+* [Bar Chart Bar]
+* [Bar Chart Value Axis ]
+* [Bar Chart Category Axis]
+* [Bar Chart Types]
+* [Bar Chart Sorting]
+
+
+## Support
+
+If you notice an error in the example code, please open an issue on [GitHub][0] repository of the entire example.
+
+Official [API documentation][1] can be found on [LightningChart][2] website.
+
+If the docs and other materials do not solve your problem as well as implementation help is needed, ask on [StackOverflow][3] (tagged lightningchart).
+
+If you think you found a bug in the LightningChart JavaScript library, please contact [email protected].
+
+Direct developer email support can be purchased through a [Support Plan][4] or by contacting [email protected].
+
+[0]: https://github.com/Arction/
+[1]: https://lightningchart.com/lightningchart-js-api-documentation/
+[2]: https://lightningchart.com
+[3]: https://stackoverflow.com/questions/tagged/lightningchart
+[4]: https://lightningchart.com/support-services/
+
+© LightningChart Ltd 2009-2022. All rights reserved.
+
+
+[Bar Chart]: https://lightningchart.com/js-charts/api-documentation/v4.2.0/interfaces/BarChart.html
+[Bar Chart Bar]: https://lightningchart.com/js-charts/api-documentation/v4.2.0/
+[Bar Chart Value Axis ]: https://lightningchart.com/js-charts/api-documentation/v4.2.0/classes/BarChartValueAxis.html
+[Bar Chart Category Axis]: https://lightningchart.com/js-charts/api-documentation/v4.2.0/classes/BarChartCategoryAxis.html
+[Bar Chart Types]: https://lightningchart.com/js-charts/api-documentation/v4.2.0/
+[Bar Chart Sorting]: https://lightningchart.com/js-charts/api-documentation/v4.2.0/
+

package.json

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+{
+  "version": "2.0.0",
+  "scripts": {
+    "build": "webpack --mode production",
+    "start": "webpack serve"
+  },
+  "license": "MIT",
+  "private": true,
+  "main": "./src/index.js",
+  "devDependencies": {
+    "clean-webpack-plugin": "^4.0.0",
+    "copy-webpack-plugin": "^10.0.0",
+    "html-webpack-plugin": "^5.5.0",
+    "webpack": "^5.64.4",
+    "webpack-cli": "^4.9.1",
+    "webpack-dev-server": "^4.6.0",
+    "webpack-stream": "^7.0.0"
+  },
+  "dependencies": {
+    "@arction/lcjs": "^4.1.1",
+    "@arction/xydata": "^1.4.0"
+  },
+  "lightningChart": {
+    "eID": "1400"
+  }
+}

src/index.js

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+/*
+ * A histogram of a normally distributed data.
+ */
+
+const lcjs = require('@arction/lcjs')
+
+const {
+    lightningChart,
+    AxisTickStrategies, 
+    BarChartTypes,
+    BarChartSorting,
+    Themes
+} = lcjs
+
+const numberOfBins = 100
+const numberOfDataPoints = 50000
+
+// Function for generating normally distributed data
+const generateGaussianRandom = (length) => {
+  const samples = []
+  for (let i = 0; i < length; i++) {
+    let u = 0, v = 0, s = 0
+    while (s === 0 || s >= 1) {
+      u = Math.random() * 2 - 1
+      v = Math.random() * 2 - 1
+      s = u * u + v * v
+    }
+    const temp = Math.sqrt(-2 * Math.log(s) / s)
+    const sample = u * temp
+    samples.push(sample)
+  }
+  return samples
+}
+
+// Function for calculating the histogram bins from 1D numerical array
+const calculateHistogramBins = (data, numberOfBins) => {
+  const minValue = Math.min(...data)
+  const maxValue = Math.max(...data)
+  const binSize = (maxValue - minValue) / numberOfBins
+
+  // Calculate bin intervals
+  const bins = []
+  for (let i = 0; i < numberOfBins; i++) {
+    const binStart = minValue + i * binSize
+    const binEnd = minValue + (i + 1) * binSize
+    bins.push({
+      binStart: Math.round(binStart * 100) / 100,
+      binEnd: Math.round(binEnd * 100) / 100,
+      values: Array(),
+    })
+  }
+  bins[numberOfBins - 1].binEnd = maxValue
+
+  // Map data to bins
+  data.forEach(value => {
+    const binIndex = Math.floor((value - minValue) / binSize);
+    if (binIndex >= 0 && binIndex < numberOfBins) {
+      bins[binIndex].values.push(value);
+    }
+  })
+
+  // Create input data for bar chart
+  const barChartData = []
+  bins.forEach(interval => {
+    barChartData.push({
+      category: `${
+        (interval.binStart + (interval.binStart === minValue ? 0 : 0.01)).toFixed(2)}—${
+          interval.binEnd < 0 ? `(${interval.binEnd.toFixed(2)})` : interval.binEnd.toFixed(2)}`,
+      value: interval.values.length
+    })
+  })
+  return barChartData
+}
+
+// Generate the data
+const values = generateGaussianRandom(numberOfDataPoints)
+const histogramData = calculateHistogramBins(values, numberOfBins)
+
+const barChart = lightningChart().BarChart({ 
+  // theme: Themes.darkGold
+  type: BarChartTypes.Vertical
+})
+  .setTitle('Histogram')
+  .setSorting(BarChartSorting.Disabled)
+  .setValueLabels(undefined)
+  .setData(histogramData)
+  .setCursorResultTableFormatter((builder, category, value, bar) => builder
+     .addRow('Range:', '', category)
+     .addRow('Amount of values:', '', bar.chart.valueAxis.formatValue(value))
+  )
+
+const barDiv = barChart.engine.container
+
+const label = document.createElement('label')
+barDiv.append(label)
+label.innerHTML = "Number of bins:"
+label.style.position = "relative"
+
+const binInput = document.createElement('input')
+barDiv.append(binInput)
+barChart.setTitleMargin({top: 25, bottom: -10})
+binInput.type = "number"
+binInput.min = "1"
+binInput.max = "1000"
+binInput.value = "100"
+binInput.style.position = "relative"
+binInput.style.height = "5%"
+
+binInput.addEventListener('input', () => {
+  const inputValue = parseInt(binInput.value)
+  if (Number.isInteger(inputValue) && inputValue > 0 && inputValue <= 1000) {
+    barChart.setData([])
+    const histogramData = calculateHistogramBins(values, inputValue)
+    barChart.setData(histogramData).setSorting(BarChartSorting.Disabled)
+  }
+})
+
+// Enable grid lines
+barChart.valueAxis.setTickStrategy(AxisTickStrategies.Numeric, ticks =>
+  ticks.setMajorTickStyle(major =>
+    major.setGridStrokeStyle(
+      barChart.getTheme().xAxisNumericTicks.majorTickStyle.gridStrokeStyle
+    )
+  ).setMinorTickStyle(( tickStyle ) => 
+    tickStyle.setGridStrokeStyle(
+      barChart.getTheme().yAxisNumericTicks.minorTickStyle.gridStrokeStyle
+      )
+  )
+)
+
+// Set same color for all bars
+const bars = barChart.getBars()
+const fillSTyle = bars[0].getFillStyle()
+bars.forEach(bar => { bar.setFillStyle(fillSTyle) })