5. Openmath plots

Openmath can be used either directly or from Maxima, to plot 2d and 3d graphs. From Maxima, it will be used by the functions plot2d and plot3d, if the option [plot_format, openmath] is used. There are other plotting functions in Maxima that will only work in openmath: plotdf, openplot_curves and graph2d. All those plotting functions are documented in the Maxima Reference Manual.

A command used to create a 2d openmath plot, for example:

plot2d(sin(x), [x, -%pi, %pi], [plot_format, openmath]);

creates a window with a menu bar with the following options:

• Close. Destroys the plot window and sends the control back to Maxima.
• Config. Allows you to change some configurations of the plot.
• Replot. After configuration changes are made, this menu option should be selected, to activate the new settings.
• Zoom. Will change the behavior of the mouse so that it will allow you to zoom in on a region of the plot by clicking with the left button. Each click near a point magnifies the plot, keeping the center at the point where you clicked. Holding the Shift key while clicking, zooms out to the previous magnification.
• Dragging. Holding the right mouse button down while the cursor is moved, the plot can be moved sideways or up and down.
• Save. Can be used to save a copy of the plot in a Postscript file.
• Help. Will show a short summary of the plot window options.

By default, each plot will be opened in a new separate window. However, the plot windows can be embedded into Xmaxima's text window, by selecting the option `Plot windows -> Embedded' in the Options menu, before the plot command is issued.

The 3d plot has a menu very similar to that obtained with plot2d, but with one additional option: Rotate. Normally, if you click on the plot, it will not be enlarged, as the 2d plots. Clicking on the left button, while dragging the mouse, will rotate the plot, allowing to control two angles: azimuth and elevation.

The menu option `Zoom', will change that default behavior, making the mouse enlarge the plot, as in the 2d case. To return to the default behavior (the mouse makes the plot rotate), the Rotate button should be used.

If Xmaxima is executed from the command line, giving as argument the name of a file, it will open that file and interpret it as a plot command, with a syntax specific of openmath. The graph generated by the commands in the file will be plotted in a plot window, and the main window of Xmaxima will not be opened and no communication with Maxima will be established. An example of the contents of a file that can be passed directly to Xmaxima is the following:

plot2d -xfun "sin(A*x);cos(x)" -yradius 10
       -sliders {A=1:6} -parameters {A=1}

that file will generate a plot of a cosine function with fixed period, and a sine function with a period that can be changed by moving the slider that appears on the bottom.

the sliders option of openmath is one feature that cannot be accessed directly from plot2d in Maxima. Other examples of input files for openmath are the files `maxout.openmath' that Maxima creates; when Maxima is run from the command line, and a plotting function that involves openmath is used, the data is not passed directly to Xmaxima, but it is rather saved into that file and then xmaxima is executed with the name of that file as argument.

The strings used in those files must be properly represented as Tcl/Tk strings.

This document was generated by Viktor T. Toth on May, 30 2017 using texi2html 1.76.