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Next: Making a Hardcopy
Up: Basics
Previous: Plot the File
PLT chooses a default scale that makes all the data visible.
The examples in this section will illustrate
the Rescale command that can be used to change this scale.
Using the plot created in the previous section, enter
PLT> R X 0 5
When you enter this command, the graph is redrawn
with 0.0 on the left side and 5.0 on the right side of the viewport.
Likewise R Y 0 20 will put 0.0 on the bottom and 20.0 on the top.
If you wish to change one number without the other,
you can skip the field with commas
or terminate the line before changing the default.
For example, both
PLT> R Y 0 20 ! Set both lower and upper limit
and
PLT> R Y,,20 ! Set upper limit to 20, leaving lower unaffected
PLT> R Y 0 ! Set lower limit to 0, leaving upper unaffected
will produce the same effect.
If you wish to change both the X and Y limits,
then use
PLT> R 1 5 1 16 ! Set X-range to 1 to 5, and Y-range 1 to 16
If you wish to go back to the default scale, then use R with
no arguments:
PLT> R Y ! Will reset Y limits to default
PLT> R ! Will reset both X and Y limits to default
At any time you can find out what the current scale limits are with
PLT> R ?
Current Gap= .025
Window XLAB XMIN XMAX YLAB YMIN YMAX
1 : .9250 , 4.075 : .6250 , 16.38
PLT>
This produces a table of the current scaling parameters.
The current gap is the default size of the gap
between the edge of the data and the edge of the plot.
For the default scale, the difference between the minimum/maximum
and the data minimum/data maximum is due to the gap.
With a gap of zero, the default minimum/maximum value will
exactly match the data minimum/data maximum.
The default is to plot all plot groups into just one window
hence only one row appears in the table corresponding to that window.
The columns labeled XLAB and YLAB contain the
current x and y labels, which are currently
blank.
If you want to see what the data minimum and maximum values are
you should use
PLT> SHow Group
Grp Wind Label XData Min XData Max YData Min YData Max
1 -1 : 1.000 , 4.000 : 1.000 , 4.000
2 1 : 1.000 , 4.000 : 1.000 , 15.00
3 1 : 1.000 , 4.000 : 1.000 , 16.00
The three rows correspond to the three plot groups.
The column labeled Wind contains the window in which the group is
currently being plotted, and a negative number indicates that the
group is not actually plotted.
In this example, group 1 is used to determine the x coordinate and
so is not actually plotted.
The columns labeled YData Min and YData Max contain
the actual data minimum and maximum of that plot group.
   
Next: Making a Hardcopy
Up: Basics
Previous: Plot the File
Web Page Maintained by: Dr. Lawrence E. Brown elwin@redshift.gsfc.nasa.gov
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