function cutDateFields(oDate, iStartIndex) {
		var sMethodName,
			aFields = ["FullYear", "Month", "Date", "Hours", "Minutes", "Seconds", "Milliseconds"],
			// no need to use UI5Date.getInstance as only the UTC timestamp is used
			oDateCopy = new Date(oDate.getTime());

		for (var i = iStartIndex; i < aFields.length; i++) {
			sMethodName = "setUTC" + aFields[iStartIndex];
			oDateCopy[sMethodName].apply(oDateCopy, [0]);
		}
		return oDateCopy;
	}
Modifies the Date and sets the values with a higher index to <code>0</code>

@param {Date} oDate input date
@param {number} iStartIndex index of the value to set to <code>0</code>. Higher indices will also be set to <code>0</code>.
0: FullYear
1: Month
2: Date
3: Hours
4: Minutes
5: Seconds
6: Milliseconds
e.g. iStartIndex <code>4</code> will set Minutes, Seconds and Milliseconds to <code>0</code>
@returns {Date} copy of the date with the modified values