public void prependText(char[] formattedValue, int charsNumber) {
        if (prependedText.length > 0) {
            System.arraycopy(prependedText, 0, formattedValue, formattedValue.length - charsNumber - appendedText.length
                    - prependedText.length, prependedText.length);
        }
    }
@see #formatFloatValueWithPrependedAndAppendedText(char[], float, int, char[])
hellocharts-library/src/lecho/lib/hellocharts/formatter/ValueFormatterHelper.java