SPEX User's Manual - SRON

34 Syntax overview
par write mypar overwrite - SPEX writes all parameters for the model to a file named mypar.com.
Any previously existing file mypar.com is overwritten.
par write mypar - Same command as above, but now a new file is created. If there already exists a file
with the same filename SPEX will give an error message.
2.22 Plot: Plotting data and models
Overview
The plot command cause the plot to be (re)drawn on the graphics device. Multiple graphics devices can
be defined in one SPEX session. For example, a plot can be sent to both a postscript and a xs device.
A user can also set the number of plot frames in the currently active device(s), e.g. the data and model
can be displayed in one frame while the residuals can be displayed in a frame below. The user has to
specify what is to be plotted in in each frame.
In each plot frame, there can be different sets that can be specified by the ”set” keyword in the plot
command. For example, for the plot type data, each set corresponds to the spectrum of an instrument
or region; with this option it is therefore possible to give different instruments different colours or plot
symbols, etc., or just to omit one of the instruments from the plot.
The plot command is also used to select the axis plot units and scales as well as character commands like
font style, line weights, plot colours, etc. Finally, the plot command can also be used to dump the data
to an ascii file.
Warning: To make a plot, always start with a ”plot device” command to open any plot device you wish.
Next select a plot type using ”plot type”. After this you can give any plot commands to modify or display
the plot.
Syntax
The following syntax rules apply for plot:
plot - (Re)draws the plot on the graphics device. Take care to open at least one device first (with a ”plot
dev” command)
plot frame new - Creates a new additional plot frame, where an other plot type can be displayed (or the
same plot type but with different units). Take care to position the viewport of the new and old frames
to the desired locations.
plot frame #i - Sets frame number #i to be the currently active frame. After this command has been
issued, all plot commands will only affect the currently active frame.
plot frame delete #i - Deletes frame number #i.
plot type #a - Specifies what is to be plotted in the selected frame. #a can be any of the plot types
specified in Sect. 4.2.
plot device #a1 [#a2] - Selects a graphics device #a1 and optional file name #a2 (in the case of a
postscript or gif device). File extensions (for example .ps) should be specified. For valid devices, see
Sect. 4.1.
plot close #i - Close graphics device number #i. Note, always close a postscript device before quiting
/spex, otherwise the contents may be corrupted.
plot hlan - Make a hardcopy in landscape orientation and send it to the standard printer. Use is made
of the unix command ”lp -c filename”.
plot hpor - As above, but for portrait orientation
plot x lin - Plot the x-axis on a linear scale
plot x log - Plot the x-axis on a log scale
plot y lin - Plot the y-axis on a linear scale
plot y log - Plot the y-axis on a log scale
plot y mix #r1 #r2 - Plot the y-axis on a mixed linear/logarithmic scale; for y-values below #r1 the
data will be plotted linear, and for y-values above #r1 the data will be plotted logarithmically; the linear
part occupies the fraction of the total frame height given by #r2. See also Sect. 4.8.2.