amChartsのwordcloudで単語出現頻度を可視化する。日本語も対応

<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha256-3edrmyuQ0w65f8gfBsqowzjJe2iM6n0nKciPUp8y+7E=" crossorigin="anonymous"></script>

<script src="https://www.amcharts.com/lib/4/core.js"></script>
<script src="https://www.amcharts.com/lib/4/charts.js"></script>
<script src="https://www.amcharts.com/lib/4/plugins/wordCloud.js"></script>
<script src="https://www.amcharts.com/lib/4/themes/animated.js"></script>
<script src="/images/posts/111/world-cloud.js"></script>


<!-- スタイル -->
<style>
#chartdiv {
  width: 100%;
  height: 500px;
}
</style>

<section class="section">

<!-- グラフの描画先 -->
<div id="chartdiv"></div>

<textarea name="text" class="textarea" placeholder="e.g. Hello world" row=20>CURRUMPAW is a vast cattle range in northern New Mexico. It is a land of rich pastures and teeming flocks and herds, a land of rolling mesas and precious running waters that at length unite in the Currumpaw River, from which the whole region is named. And the king whose despotic power was felt over its entire extent was an old gray wolf.  Old Lobo, or the king, as the Mexicans called him, was the gigantic leader of a remarkable pack of gray wolves, that had ravaged the Currumpaw Valley for a number of years. All the shepherds and ranchmen knew him well, and, wherever he appeared with his trusty band, terror reigned supreme among the cattle, and wrath and despair among their owners. Old Lobo was a giant among wolves, and was cunning and strong in proportion to his size. His voice at night was well-known and easily distinguished from that of any of his fellows. An ordinary wolf might howl half the night about the herdsman's bivouac without attracting more than a passing notice, but when the deep roar of the old king came booming down the canon, the watcher bestirred himself and prepared to learn in the morning that fresh and serious inroads had been made among the herds.</textarea>

<div class="has-text-centered">
    <button id="redraw" class="button is-primary is-rounded">Redraw</button>
</div>
</section>

$(window).on('load', function () {
    loadText();
    // ボタンクリック
    $('#redraw').on('click', function () {
        loadText();
    });
});

function loadText(){
    // テキストデータ
    var sentence = $('textarea[name="text"]').val();
    // 改行を半角スペースに変換
    sentence = sentence.replace(/\r?\n/g, ' ');
    // グラフ描画
    drawWorldCloud(sentence);
}


function drawWorldCloud(sentence) {
    // アニメーションテーマを使う
    am4core.useTheme(am4themes_animated);

    var chart = am4core.create("chartdiv", am4plugins_wordCloud.WordCloud);
    var series = chart.series.push(new am4plugins_wordCloud.WordCloudSeries());

    series.accuracy = 4;
    series.step = 15;
    series.rotationThreshold = 0.7;
    series.maxCount = 200;
    series.minWordLength = 2; // 最少頻度
    series.labels.template.tooltipText = "{word}: {value}";
    series.fontFamily = "Courier New";
    series.maxFontSize = am4core.percent(30);

    // 文字列を渡すだけ
    series.text = sentence;

    // カラフルになる。
    series.colors = new am4core.ColorSet();
    series.colors.passOptions = {}; // makes it loop

    // 配置が動くようになる
    setInterval(function () {
        series.dataItems.getIndex(Math.round(Math.random() * (series.dataItems.length - 1))).setValue("value", Math.round(Math.random() * 10));
    }, 10000)
}