Convert Indian currency value to a readable comma separate value in Zoho Creator

FormatIndianCurrency.ds

string FormatIndianCurrency(float currency_val)
{
	number = "";
	frac_value = "";
	if(currency_val != null)
	{
		if(currency_val > 0.0)
		{
			// whole_value = "12345678";
			whole_value = currency_val.toString().getPrefix(".");
			separator = 3;
			visit = 0;
			str_len = whole_value.length();
			st_ind = str_len - 1;
			end_ind = str_len;
			counter = leftpad("1",str_len).replaceAll(" ","1,").toList();
			for each index i in counter
			{
				visit = visit + 1;
				number = number + whole_value.substring(st_ind,end_ind);
				if(visit == separator && st_ind != 0)
				{
					number = number + ",";
					separator = 2;
					visit = 0;
				}
				st_ind = st_ind - 1;
				end_ind = end_ind - 1;
			}
			frac_value = "." + currency_val.toString().getSuffix(".");
		}
	}
	return number.reverse() + frac_value;
}