
Graph_Pane

Definitions:

1> Data Set : consists of an array of values of a single variable. Each data 
	set has a label associated with it. The values are plotted against
	the Y-axis.

Assumptions:

1> All data sets are of equal length. 

2> All data set values  are a function of time intervals.

3> The beginning time is never less than zero.

Components:
	
1)Menu Bar: 	

a> File Menu 
	
	"View Statistics" := runs the UTEStatsViewer.Main program, for viewing
		"foo.tsv" files as graphs.
	"Close"           := calls the function ClosePreview of the abstract
		class TimeInterface which is an eventlistener on Graph_Pane for
		its container object. 
	
b> Graph Menu
	i>  Type SubMenu
		
		"Bar"   := displays a bar graph 
		"Line"  := displays a line graph
			
	ii> ReScale
		"On"    := allows the y-axis to be rescaled whenever the 
			maximum plotted value changes.  
		"Off"   := retains the current scale of the y-axis.

c> Data Sets
	"All"   := displays all the data sets.
	"None"  := clears the graph of all data.

d> Zoom
	"In"    := increases the width of the graph area by a factor of two 
		depending on the current size. The limit is a width of
		(2 ^ 14) pixels.
	"Out:   := decreases the width of the graph area by a factor of two.
		The minimum width is 512 pixels.
	"Reset" := resets the graph to the minimum display width of 512 
	 	pixels.

e> Legend
	"Display" := shows the dialog with a list of labels for each data set.
	"Hide"    := hides the dialog.

2) Title Pane 
	shows the title of the graph. Also has a time textfield which displays
	the time corresponding to the position of the mouse on the graph.

3) Graph
	A mouse click on the graph fixes that point as the display marker. 
	When a zooming in operation is done the point remains fixed while the 
	graph expands. when a zooming out operation is done the point remains
	visible but not necessarily fixed.

4) Legend Dialog
	Allows user to select data values for display on the graph. Allows for 
	multiple list elements to be selected or deselected. Clicking on a 
	list element or several (using the cntrl/shift keys) only allows one
	to select that element for an operation.
	
a) Buttons
	"Select" := the selected list element (data set) is not 
		displayed on the graph if it was already in the selected 
		state or vice versa.
	"All"    := all data sets are selected for display on the graph.
	"None"   := the data sets are removed from the graph.
	"Change Color"  := allows one to change the color of the data set.

			 
	
		
	




