This section assumes that IFEFFIT has been built with the PGPLOT plotting package. This is available for both Unix and Win32 systems, though support for Win32 is still experimental. For Unix systems, this library has to be installed prior to installing IFEFFIT, which is fairly easy to do for most systems. IFEFFIT can also be built without this plotting package.
Plotting in IFEFFIT is encapsulated in a handful of commands, the most important of which is the plot() command, which takes two required arguments for the ordinate (x-array) and abscissa (y-array) to be plotted, and take a large set of optional arguments. A simple plot can be done like this:
Ifeffit> plot(cu.energy, cu.xmu)The plot command will overplot , so that a second plot command:
Ifeffit> plot(cu.energy, cu.bkg)will add a trace of the background to the earlier plot. To force the current plot to be erase before plotting, you'd say
Ifeffit> newplot(cu.energy, cu.xmu)Each x-y trace plotted has a color and line style associated with it. You can set the values in these table explicitly for each particular plot command by specifying the color or linestyle (or both) directly:
Ifeffit> plot(cu.energy, cu.xmu, color = blue) Ifeffit> plot(cu.energy, cu.bkg, color = red, style = dashed)You can also pre-define the color and linestyle for the first, second, ...trace ahead of time
Ifeffit> color(1=blue, 2 = red, 3 = black) Ifeffit> linestyle(1=solid, 2=dashed, 3 = linespoints2)so that the first trace plotted is a solid blue line, and the second is a dashed red line, and the third a black line with a '+' at each data point.
The allowed color names are the 'standard X Windows' colors found in the rgb.txt file on your system. Most common color names are supported, as well as the descriptive if ambiguous 'X Windows' names like "lightsalmon3" and "bisque". You may also use the conventional hexadecimal representation of the color with a string of '#RRGGBB'.
Allowed line styles are 'solid', 'dashed', 'dotted', 'points', and 'linespointsN' where N = 1, 2, 3, .... The latter will draw a line connecting symbols at each data point, with symbols '.', '+', '*','o', 'X', squares, and triangles for N=1,2,3,4,5, and 6. Setting the color and linestyle tables like this is often a convenient thing to do in a macro (see section 9) or start-up file.
For Unix using X Windows, the PGPLOT window supports getting the (x,y) coordinates from the plot window using the mouse device. To use this within IFEFFIT, you'd type cursor at the command prompt, and then click on the desired point on the plotting window. The IFEFFIT variables cursor_x and cursor_y will contain the (x,y) coordinates. The zoom command will let you view a selected region of the plot by clicking the mouse on the corners of the area to zoom in on. Many more plotting options exist - please consult the Reference Guide.