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Plot a coordinate box

A coordinated box (axes) can be drawn with the routine PCAXES  (PTAXES)  or PCFRAM  (PTFRAM) . PCFRAM  (PTFRAM)  uses the device setting done by PCOPEN (PTOPEN) and you will have to give the values for the big tick marks and the small tick marks (no defaults!). PCFRAM (PTFRAM) is used in all MIDAS application programs. Hence, the axes drawn by PCFRAM (PTFRAM) in your application program will look identical to the axes drawn by using the MIDAS command PLOT/AXES.

PCAXES (PTAXES) uses also the device setting done by PCOPEN (PTOPEN), but it adjusts the scaling so that the quotes, labels and title will fit into the device viewport. The big tick marks and the small tick marks are calculated and this routine offers a lot of nice options.

Note that PCAXES (PTAXES) has to be called before plotting any data or text, while PCFRAM (PTFRAM) may be called before or after plotting the data.

After having the coordinate box drawn by one of the axes routines the graphics system is set to the so-called USER mode, the user (world) coordinate system. All subsequent plotting activities are assumed to take place in this coordinate system and hence all coordinates should be in user coordinates. To switch to the NORMalized (clip) coordinate system (that runs from 0 to 1 in both the x- and y-direction of the graphics device) one has to use the specific AGL routine AGSSET.


next up previous contents index
Next: Plot data Up: Graphics Interfaces Previous: Open a device
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Last update: 1998-10-23