setText(text : string) {
    this.wordService.GetWordsCount(text).then((list) => {

        // Give exponential weight to each word count to emphasize
        // small differences. A better algorithm could find the best power
        // based on the variance.
        let scale = list.map((ww) => new WordWeight(ww.word, Math.pow(ww.count,2)));

        // find maximum weight in the array.
        let max = scale.map((ww) => ww.count).
            reduce((max, cur) => {
                return Math.max(max, cur);
            }, 0);

        // scale each word to a fixed size (this.maxSize) so the more
        // important word will be this.maxSize and the others will be smaller
        // accordingly.
        scale = scale.map((ww) => new WordWeight(ww.word, (ww.count / max) * this.maxSize));

        // prepare the array required by WordCloud.
        let outarray = scale.map((ww) => [ww.word, ww.count]);

        // Call WordCloud pointing it to our canvas.
        WordCloud(document.getElementById("my_canvas"), {
            list: outarray,
            gridSize: 1,
            minSize: 0,
        });

    });
}