x2label:

Synopsis: Set the x-axis text label for the top x-axis.

Syntax: xlabel2 ( "string", I )

Description:

	Set the x-axis label for the I:th plot-window. 
	x2label() uses the top x-axis.
	If x2label() is used without any arguments, then the
	x-axis label is set to the null-string. 
	
	If 'I' is not specified the default plot-window is used, see defplotwin().

See Also: xlabel, ylabel, y2label, zlabel, label, title
