Institut für Astronomie und Astrophysik
Abteilung AstronomieSand 1, D-72076 Tübingen, Germany
plots data/model of fit
top - (optional) Defines the plot type to draw in the upper part of the plot window. bottom - (optional) Defines the plot type to draw in the lower part of the plot window. panelnum - If instead of bottom a integer number is given the panel with this number is set (starting from 0).
The plots to be inserted in the top/bottom panels are defined with plot types defining what to plot. There are some plot types available (and could be extended just as in case of fit models). Syntax: > [+|-]<plot type>["[parameter]"][:group]... > ...[+<plot type>["[parameter]"][:group]] With: - add/remove:If the plot type is prepended with "+" the new plot types are added to the current ones. If the plot type is prepended with "-" this plot type is removed. For this case wildcards are allowed to remove more than one plot type.
> plot,data+model > plot,-mod* -> remove the model plot type. - plot type: defining what to plot (refer below) - parameter: defining special options to be passed to the plot type driver. These are usually those accepted by the IDL oplot command, e.g. linestyle. The format is: keyword=value. It is possible to define several such parameters which must be separated by ";". If the assignment "=value" is not given the value =1 will be used (setting flags).
plot, data[linestyle=3;psym=-4;noerror] Remark: Options set with setplot override these parameters. - group: Defines for the plot type which data group to use. This allows to plot several groups in a single plot window.
> plot, data+model... -> Draw data and model in the same panel. > plot, data:2+data:3 -> Draw data from group 2,3 to panel. > plot, data[linestyle=3;psym=-3]+model -> Draw data plus underlying model, which is formated with different symbol/linestyle.
The "+" adds several plot types in the same panel. In this case each will be drawn in a different color (refer also to the plot types itself). The optional ":<group>" defines the group for the specific plot type to look data/model for. Common plot types are "data" - draw the data as is "model"- draw the computed model with current parameters "res" - Residuum between data/model "delchi" - Same but in units of 1 sigma Available plot types can be listed with the command help,plot,all while a specific plot type can be shown with the command help,plot,<plot type>.
/quiet - Do not print plot informations. /noeraase - Do not delete window (useful for plotting as a client procedure)
All options may be set with the "set" command. The command prefix is "plot".
Plotting may be influenced by some general plot parameters set with the setplot command. For all plot styles following setplot identifier will be applicable (and must be defined for plot panel 0): weight - A integer number which defines how the height should be distributed among different panels. For this all weights are summed up; and each panel gets a share according its weight from the total sum. For example with top panel of weight 2 and bottom panel of weight 1 will set 2/3 of the available height at top panel and 1/3 at bottom panel (this is the default). topsep - Floating number between 0..1 defining margin of plot to top (either frame or plot above). This must include sufficient place for title/subtitle text. Default is 0.05. bottomsep - Floating number between 0..1 defining margin of plot to bottom (either frame or plot below). This must include sufficient space for x-axis text/sub-text. Default is 0.1. rmargin - Floating number between 0..1 defining margin of plot to right side. This must include sufficient space for right y-axis text (if any). Default is 0.05. lmargin - Floating number between 0..1 defining margin of plot to left side. This must include sufficient space for left y-axis text/tick labels. Default is 0.1. xfree - Flag (0/1). If set the x-range is computed independent for each panel (not recommended for interactive plot tools, e.g. iplot/wplot). Default is off (0). position - 4-vector containing edge coordinates of panel to plot. Coordinates are values between 0..1. Setting this option overrides the default algorith using the top/bottomsep/r/lmargin and weigth keywords described above. background - The background color for all plots. This is common for all panels and can not be set separately :-< startcolor - First color number used to plot frame/data. Must be adapted to currently used color table. Default: 255. deltacolor - Decrease of color to apply for distinct plot types/data sets. Default: 23. startlinestyle - First line style used to plot frame/data. Default: 0. Must not exceed 5. deltalinestyle - Increase of line styles for distinct plot types/data sets. May be positive or negative integer number. Default: 0 (no change). startpsym - First point symbol used to plot frame/data. Default: -4. Should not exceed -7..7. If psym is negative lines are drawn, if positive, not (refer IDL PLOT command). Userdefined symbols (8) are not supported. deltapsym - Increase of point symbols for distinct plot types/data sets. May be positive or negative integer number. Default: 0 (no change). If psym exceeds -7..7 during plot different plot types it will be set at 0 (no symbol). Therefore plotting all data sets with lines it is recomended to set deltapsym at a negative value (to decrease and restart from 0). zbuff - Use the Z Buffer device for plot production. The practical use is for 3-dim plots. The Z Buffer device essentially is able to check which object (even axis lines, text or data) is behind another object and must not be drawn. This is especially usefull when: - Combining several shaded objects, possibly with surface or contour. - Generating high quality plot 3-dim plot images. The drawback is that the generated (postscript) images are pixelated, i.e. the quality depends on the resolution/image size. Also fonts are not always drawn properly. This means: If one prints zbuffer generated plots into a file she has to look - reasonable resolution (s.b.) - A proper line thickness (setplot keywords thick, xthick,ythick,zthick). - A scaleable font. System fonts usually look poor. It is recomended to use the setplot keyword font=1. maxres - Using the Z Buffer device with this keyword defines the maximal number of pixels in X direction. Default are 5000. The pixel in Y direction are set according the plot aspect ratio. tex - Use TexToIDL to convert the parameter text from TeX syntax into IDL strings. This allows to access mathematical symbols like \chi=Chi, \Delta,\pi etc. It is recomended to use this parameter instead of calling textoidl() manually. The latter causes problems when printing into postscript files because the IDL codes for plot fonts (!p.font = -1) and hardware fonts (!p.font = 0) are different. enhanced - Switch on enhanced plot facilities (see ENHANCED PLOTTING).
Enhanced plotting is intended for 2-D plotting only (because 1-D plots do not need to shade/mask/combine images). The plot may be a combination of different separate plot images. This feature is enabled using the "enhanced" keyword. After this some plot operators are available which take each plot type as a separate unit which can be combined to create complex images. In standard mode only the "+" operator is available which simply overlays several plot images. In enhanced mode following operators are implemented: + - standard case: execute plot type on current plot device. This is the only operator which acknowledges the z buffer device. ^ - add two images in respect of their colors. May be used to simulate transparency by adding image parts which were hidden. * - multiply colors of image. May be used to enhance/diminish colors. It is possible to multiply an image with a number to change the color space. & - mask parts of image. This means that for a & b the image b is shown where image b is not background color, otherwise a is shown. Usefull to replace parts of image with other parts. There are some additional keyword parameters which can be used to influence the plot result: ctable - Defines the color table to use. Therefore a plot may consist of plot images created with different color tables ;-) background - Defines the background color for which the plot is considered to be transparent. This is important for the "&" - Operator to mask certain parts of the image.
The enhanced mode may be used to circumvent problems arising from Z Buffer use. A detailed tutorial is described at: http://www.sljus.lu.se/stm/IDL/Surf_Tips/ by Struan Gray. Here some basic examples: > setplot,enhanced > setplot,zbuff > plot,data2[shade] & data2[surf] -> avoid submarining of surface lines in shade plot. Actually the surface *replaces* the shade. > plot,data[shade]:0*0.5 ^ data2[shade]:1*0.5 -> plot data sets of group 0 and 1 in a transparent manner > plot,data2[shade,ctable=1]:0+data2[shade,shading=0]:1 ^ > data2[shade,ctable=3]:1+data2[shade,shading=0]:0 -> plot data set 0 in blue color and data set 1 in red color, masking each other. Remarks: The enhanced mode has some drawbacks. One is that is significant slower than the standard mode (because each image must be read and processed separately). The other problem arises from the fact that the image always is pixellated; plotting out to a postscript device results in the same problems as the use of the Z-Buffer device (which should be used in enhanced mode anyway).
Last plot ranges/plot type will be stored if no new is given.
> plot, data,delchi -> plot data and chi difference in different panels.
$Id: cafe_plot.pro,v 1.34 2004/07/30 15:52:36 goehler Exp $
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