function lerp$1(normalizedValue, colors, fullOutput) {
    if (!(colors && colors.length)
        || !(normalizedValue >= 0 && normalizedValue <= 1)
    ) {
        return;
    }

    var value = normalizedValue * (colors.length - 1);
    var leftIndex = Math.floor(value);
    var rightIndex = Math.ceil(value);
    var leftColor = parse(colors[leftIndex]);
    var rightColor = parse(colors[rightIndex]);
    var dv = value - leftIndex;

    var color = stringify(
        [
            clampCssByte(lerpNumber(leftColor[0], rightColor[0], dv)),
            clampCssByte(lerpNumber(leftColor[1], rightColor[1], dv)),
            clampCssByte(lerpNumber(leftColor[2], rightColor[2], dv)),
            clampCssFloat(lerpNumber(leftColor[3], rightColor[3], dv))
        ],
        'rgba'
    );

    return fullOutput
        ? {
            color: color,
            leftIndex: leftIndex,
            rightIndex: rightIndex,
            value: value
        }
        : color;
}
@param {string} color
@param {number=} h 0 ~ 360, ignore when null.
@param {number=} s 0 ~ 1, ignore when null.
@param {number=} l 0 ~ 1, ignore when null.
@return {string} Color string in rgba format.
@memberOf module:zrender/util/color