Backend API
        
    import React from 'react';
import {
  PolarChart,
  CommonSeriesSettings,
  Series,
  CommonAnnotationSettings,
  Annotation,
  ArgumentAxis,
  Strip,
  Legend,
} from 'devextreme-react/polar-chart';
import { dataSource, maxDay, minNight } from './data.ts';
const maxTempText = `Highest temperature: ${maxDay.day} °C`;
const minTempText = `Lowest temperature: ${minNight.night} °C`;
function App() {
  return (
    <PolarChart
      id="radarChart"
      dataSource={dataSource}
      title="Average temperature in London"
    >
      <CommonSeriesSettings
        type="bar"
        opacity={0.75}
      />
      <Series
        valueField="day"
        name="Day"
        color="#fdff5e"
      />
      <Series
        valueField="night"
        name="Night"
        color="#0f3b59"
      />
      <CommonAnnotationSettings
        opacity={0.7}
        arrowLength={0}
        type="text"
      />
      <Annotation
        angle={45}
        radius={180}
        text="WINTER"
      />
      <Annotation
        angle={135}
        radius={180}
        text="SPRING"
      />
      <Annotation
        angle={225}
        radius={180}
        text="SUMMER"
      />
      <Annotation
        angle={315}
        radius={180}
        text="FALL"
      />
      <Annotation
        argument={maxDay.arg}
        opacity={1}
        offsetX={105}
        paddingTopBottom={15}
        paddingLeftRight={15}
        text={maxTempText}
        series="Day"
      />
      <Annotation
        argument={minNight.arg}
        opacity={1}
        offsetX={105}
        paddingTopBottom={15}
        paddingLeftRight={15}
        text={minTempText}
        series="Night"
      />
      <ArgumentAxis>
        <Strip
          startValue="December"
          endValue="February"
          color="#0076d1">
        </Strip>
        <Strip
          startValue="March"
          endValue="May"
          color="#3ca3b0">
        </Strip>
        <Strip
          startValue="June"
          endValue="August"
          color="#3fbc1e">
        </Strip>
        <Strip
          startValue="September"
          endValue="November"
          color="#f0bb00">
        </Strip>
      </ArgumentAxis>
      <Legend
        horizontalAlignment="center"
        verticalAlignment="bottom"
      />
    </PolarChart>
  );
}
export default App;
    
    import React from 'react';
import {
  PolarChart,
  CommonSeriesSettings,
  Series,
  CommonAnnotationSettings,
  Annotation,
  ArgumentAxis,
  Strip,
  Legend,
} from 'devextreme-react/polar-chart';
import { dataSource, maxDay, minNight } from './data.js';
const maxTempText = `Highest temperature: ${maxDay.day} °C`;
const minTempText = `Lowest temperature: ${minNight.night} °C`;
function App() {
  return (
    <PolarChart
      id="radarChart"
      dataSource={dataSource}
      title="Average temperature in London"
    >
      <CommonSeriesSettings
        type="bar"
        opacity={0.75}
      />
      <Series
        valueField="day"
        name="Day"
        color="#fdff5e"
      />
      <Series
        valueField="night"
        name="Night"
        color="#0f3b59"
      />
      <CommonAnnotationSettings
        opacity={0.7}
        arrowLength={0}
        type="text"
      />
      <Annotation
        angle={45}
        radius={180}
        text="WINTER"
      />
      <Annotation
        angle={135}
        radius={180}
        text="SPRING"
      />
      <Annotation
        angle={225}
        radius={180}
        text="SUMMER"
      />
      <Annotation
        angle={315}
        radius={180}
        text="FALL"
      />
      <Annotation
        argument={maxDay.arg}
        opacity={1}
        offsetX={105}
        paddingTopBottom={15}
        paddingLeftRight={15}
        text={maxTempText}
        series="Day"
      />
      <Annotation
        argument={minNight.arg}
        opacity={1}
        offsetX={105}
        paddingTopBottom={15}
        paddingLeftRight={15}
        text={minTempText}
        series="Night"
      />
      <ArgumentAxis>
        <Strip
          startValue="December"
          endValue="February"
          color="#0076d1"
        ></Strip>
        <Strip
          startValue="March"
          endValue="May"
          color="#3ca3b0"
        ></Strip>
        <Strip
          startValue="June"
          endValue="August"
          color="#3fbc1e"
        ></Strip>
        <Strip
          startValue="September"
          endValue="November"
          color="#f0bb00"
        ></Strip>
      </ArgumentAxis>
      <Legend
        horizontalAlignment="center"
        verticalAlignment="bottom"
      />
    </PolarChart>
  );
}
export default App;
    
    import React from 'react';
import ReactDOM from 'react-dom';
import App from './App.tsx';
ReactDOM.render(
  <App />,
  document.getElementById('app'),
);
    
    export const dataSource = [{
  arg: 'December',
  day: 7,
  night: 3,
}, {
  arg: 'January',
  day: 6,
  night: 2,
}, {
  arg: 'February',
  day: 7,
  night: 3,
}, {
  arg: 'March',
  day: 10,
  night: 3,
}, {
  arg: 'April',
  day: 14,
  night: 5,
}, {
  arg: 'May',
  day: 18,
  night: 8,
}, {
  arg: 'June',
  day: 21,
  night: 11,
}, {
  arg: 'July',
  day: 22,
  night: 13,
}, {
  arg: 'August',
  day: 21,
  night: 13,
}, {
  arg: 'September',
  day: 19,
  night: 11,
}, {
  arg: 'October',
  day: 15,
  night: 8,
}, {
  arg: 'November',
  day: 10,
  night: 4,
}];
export const maxDay = dataSource
  .reduce((prev, current) => (prev.day >= current.day ? prev : current));
export const minNight = dataSource
  .reduce((prev, current) => (prev.day <= current.day ? prev : current));
    
    window.exports = window.exports || {};
window.config = {
  transpiler: 'ts',
  typescriptOptions: {
    module: 'system',
    emitDecoratorMetadata: true,
    experimentalDecorators: true,
    jsx: 'react',
  },
  meta: {
    'react': {
      'esModule': true,
    },
    'typescript': {
      'exports': 'ts',
    },
    'devextreme/time_zone_utils.js': {
      'esModule': true,
    },
    'devextreme/localization.js': {
      'esModule': true,
    },
    'devextreme/viz/palette.js': {
      'esModule': true,
    },
    'openai': {
      'esModule': true,
    },
  },
  paths: {
    'npm:': 'https://cdn.jsdelivr.net/npm/',
    'bundles:': '../../../../bundles/',
    'externals:': '../../../../bundles/externals/',
  },
  defaultExtension: 'js',
  map: {
    'ts': 'npm:plugin-typescript@8.0.0/lib/plugin.js',
    'typescript': 'npm:typescript@4.2.4/lib/typescript.js',
    'jszip': 'npm:jszip@3.10.1/dist/jszip.min.js',
    'react': 'npm:react@17.0.2/umd/react.development.js',
    'react-dom': 'npm:react-dom@17.0.2/umd/react-dom.development.js',
    'prop-types': 'npm:prop-types/prop-types.js',
    'rrule': 'npm:rrule@2.6.4/dist/es5/rrule.js',
    'luxon': 'npm:luxon@3.4.4/build/global/luxon.min.js',
    'es6-object-assign': 'npm:es6-object-assign',
    'devextreme': 'npm:devextreme@link:../../packages/devextreme/artifacts/npm/devextreme/cjs',
    'devextreme-react': 'npm:devextreme-react@link:../../packages/devextreme-react/npm/cjs',
    'devextreme-quill': 'npm:devextreme-quill@1.7.6/dist/dx-quill.min.js',
    'devexpress-diagram': 'npm:devexpress-diagram@2.2.24/dist/dx-diagram.js',
    'devexpress-gantt': 'npm:devexpress-gantt@4.1.64/dist/dx-gantt.js',
    'inferno': 'npm:inferno@8.2.3/dist/inferno.min.js',
    'inferno-compat': 'npm:inferno-compat/dist/inferno-compat.min.js',
    'inferno-create-element': 'npm:inferno-create-element@8.2.3/dist/inferno-create-element.min.js',
    'inferno-dom': 'npm:inferno-dom/dist/inferno-dom.min.js',
    'inferno-hydrate': 'npm:inferno-hydrate/dist/inferno-hydrate.min.js',
    'inferno-clone-vnode': 'npm:inferno-clone-vnode/dist/inferno-clone-vnode.min.js',
    'inferno-create-class': 'npm:inferno-create-class/dist/inferno-create-class.min.js',
    'inferno-extras': 'npm:inferno-extras/dist/inferno-extras.min.js',
    '@preact/signals-core': 'npm:@preact/signals-core@1.8.0/dist/signals-core.min.js',
    'devextreme-cldr-data': 'npm:devextreme-cldr-data@1.0.3',
    // SystemJS plugins
    'plugin-babel': 'npm:systemjs-plugin-babel@0.0.25/plugin-babel.js',
    'systemjs-babel-build': 'npm:systemjs-plugin-babel@0.0.25/systemjs-babel-browser.js',
    // Prettier
    'prettier/standalone': 'npm:prettier@2.8.8/standalone.js',
    'prettier/parser-html': 'npm:prettier@2.8.8/parser-html.js',
  },
  packages: {
    'devextreme': {
      defaultExtension: 'js',
    },
    'devextreme-react': {
      main: 'index.js',
    },
    'devextreme-react/common': {
      main: 'index.js',
    },
    'devextreme/events/utils': {
      main: 'index',
    },
    'devextreme/common/core/events/utils': {
      main: 'index',
    },
    'devextreme/localization/messages': {
      format: 'json',
      defaultExtension: 'json',
    },
    'devextreme/events': {
      main: 'index',
    },
    'es6-object-assign': {
      main: './index.js',
      defaultExtension: 'js',
    },
  },
  packageConfigPaths: [
    'npm:@devextreme/*/package.json',
  ],
  babelOptions: {
    sourceMaps: false,
    stage0: true,
    react: true,
  },
};
System.config(window.config);
// eslint-disable-next-line
const useTgzInCSB = ['openai'];
    
    import React from 'react';
import ReactDOM from 'react-dom';
import App from './App.js';
ReactDOM.render(<App />, document.getElementById('app'));
    
    export const dataSource = [
  {
    arg: 'December',
    day: 7,
    night: 3,
  },
  {
    arg: 'January',
    day: 6,
    night: 2,
  },
  {
    arg: 'February',
    day: 7,
    night: 3,
  },
  {
    arg: 'March',
    day: 10,
    night: 3,
  },
  {
    arg: 'April',
    day: 14,
    night: 5,
  },
  {
    arg: 'May',
    day: 18,
    night: 8,
  },
  {
    arg: 'June',
    day: 21,
    night: 11,
  },
  {
    arg: 'July',
    day: 22,
    night: 13,
  },
  {
    arg: 'August',
    day: 21,
    night: 13,
  },
  {
    arg: 'September',
    day: 19,
    night: 11,
  },
  {
    arg: 'October',
    day: 15,
    night: 8,
  },
  {
    arg: 'November',
    day: 10,
    night: 4,
  },
];
export const maxDay = dataSource.reduce((prev, current) =>
  (prev.day >= current.day ? prev : current));
export const minNight = dataSource.reduce((prev, current) =>
  (prev.day <= current.day ? prev : current));
    
    <!DOCTYPE html>
<html lang="en">
  <head>
    <title>DevExtreme Demo</title>
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=5.0" />
    <link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/25.1.6/css/dx.light.css" />
    <link rel="stylesheet" type="text/css" href="styles.css" />
    <script src="https://cdn.jsdelivr.net/npm/core-js@2.6.12/client/shim.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/systemjs@0.21.3/dist/system.js"></script>
    <script type="text/javascript" src="config.js"></script>
    <script type="text/javascript">
      System.import("./index.tsx");
    </script>
  </head>
  <body class="dx-viewport">
    <div class="demo-container">
      <div id="app"></div>
    </div>
  </body>
</html>
    
    #radarChart {
  height: 600px;
}
    
                You can place annotations at specific coordinates or anchor them to PolarChart elements. This demo illustrates the following annotation placement methods:
- Angle and radius properties specify the position of annotations with season names.
- Annotations with temperatures are anchored to series points, and the offsetX, paddingTopBottom, and paddingLeftRight properties specify their position.
For more information on annotation settings, refer to the annotations[] help topic.