Function getPrecision

test/lib/testHelper.js:3196–3221

* Copied from src/util/number.ts

(val)

     * Copied from src/util/number.ts
     */
    function getPrecision(val) {
        val = +val;
        if (isNaN(val)) {
            return 0;
        }

        // It is much faster than methods converting number to string as follows
        //      let tmp = val.toString();
        //      return tmp.length - 1 - tmp.indexOf('.');
        // especially when precision is low
        // Notice:
        // (1) If the loop count is over about 20, it is slower than `getPrecisionSafe`.
        //     (see https://jsbench.me/2vkpcekkvw/1)
        // (2) If the val is less than for example 1e-15, the result may be incorrect.
        //     (see test/ut/spec/util/number.test.ts `getPrecision_equal_random`)
        if (val > 1e-14) {
            var e = 1;
            for (var i = 0; i < 15; i++, e *= 10) {
                if (Math.round(val * e) / e === val) {
                    return i;
                }
            }
        }

        return getPrecisionSafe(val);
    }

    /**
     * Copied from src/util/number.ts