code: public final boolean setPointAt(int groupIndex, int indexInGroup, double x, double y) {
  		return setPointAt(groupIndex, indexInGroup, x, y, false);
  	}
docs: Set the specified point at the given index in the specified group.
  
  @param groupIndex is the index of the group
  @param indexInGroup is the index of the ponit in the group (0 for the
  first point of the group...).
  @param x is the new value.
  @param y is the new value.
  @return <code>true</code> if the point was set, <code>false</code> if
  the specified coordinates correspond to the already existing point.
  @throws IndexOutOfBoundsException in case of error