Setting the Plot Window Limits
XYPLOT automatically sets the plot window limits from the
minimum and maximum values in all the data. You may
specify new window limits by
- using the plot cursor to define a box
- manually entering new window limits
The first method is a quick way
to zoom in on a region of interest. You can inspect fine detail
in whatever region interests you. The
second method is useful to
make the limits and tic spacings meaningful numbers for the user.
It is also useful because in XYPLOT the x limits of the
plot window serve to select data for operations
such as storing or removing parts of a data set, calculating
areas, or making a polynomial fit. This is in analogy to selecting
text for block operations in a word processing program.
Setting window limits with the plot cursor
You may zoom in on part of the plot window with the mouse
or keypad.
For Systems With a Mouse
Move the cursor to point at one corner of a region
you want to see in more detail. Hold down the
left mouse button and move the mouse to
define a box. Release the button and the graph will be
redrawn with the new window limits. The portion of the
plot window that had been inside the box will now fill
the entire plot window.
For Systems Without a Mouse
Use the cursor keys to locate the plot cursor at one corner
of the box you want to define and then press Enter.
The keypad arrows now control the size of the box.
Press Enter again and the portion of the plot window
inside the box will fill the entire window.
Illustrated Example
Press the Esc key to return to a previous level of
display limits. Up to four levels may be stacked. Esc will
return through them one at a time.
Setting the window limits by input
Point with the mouse arrow cursor to the icon < >
and click the left mouse button, or press the key
E, and you will be prompted for the new window limits
Enter new window limits x1, y1, x2, y2:
where (x1, y1) is the lower left corner and
(x2, y2) is the upper right corner of the window.
You need not specify all of the new coordinates. For example,
to change only y1 and y2, you could enter just
the new values of y1 and y2.
,y1,,y2
Example
Assume the plot window limits are set to (-10, 0) for the
lower left corner, and (10, 100) for the upper right
corner. To change the limits to (-20, 0) and (20, 100)
- Click on the icon < > with the left mouse button
or press the E key.
- Enter -20,0,20,100 at the prompt.
The display will appear with the new window limits.
The icon now appears as <*>.
To return to the previous level of display limits, point at <*>
and press the right mouse button, or press the Esc
key.
Since you did not change the y limits in this example,
you could also have entered
-20,,20
and the unspecified limits will default to the current ones.