Plotting support is only available in the graphical GNOME version. All plotting accessible from the graphical interface is available from the Create Plot window. You can access this window by either clicking on the Plot button on the toolbar or selecting Plot from the Calculator menu. You can also access the plotting functionality by using the plotting functions of the GEL language. See the chapter on GEL Basics to find out how to enter expressions that &appname; understands.

# Line Plots

To graph real valued functions of one variable open the Create Plot window. You can also use the LinePlot function on the command line (see its documentation).

Once you click the Plot button, a window opens up with some notebooks in it. You want to be in the "Function line plot" notebook tab, and inside you want to be on the "Functions / Expressions" notebook tab.

## Create Plot Window

Shows the line plotting window.

Into the text boxes just type in expressions where `x` is the independent variable. You can also just give names of functions such as `cos` rather then having to type `cos(x)`. You can graph up to ten functions. If you make a mistake and &appname; cannot parse the input it will signify this with a warning icon on the right of the text input box where the error occured, as well as giving you an error dialog. You can change the ranges of the dependent and independent variables in the bottom part of the dialog.

Pressing the Plot button produces the following graph.

## Plot Window

The graph produced.

From here you can print out the plot, create encapsulated postscript or a PNG version of the plot or change the zoom. If the dependent axis was not set correctly you can have &appname; fit it by finding out the extrema of the graphed functions.

For plotting using the command line see the documentation of the LinePlot function.

# Parametric Plots

In the create plot window, you can also choose the Parametric notebook tab to create two dimensional parametric plots. This way you can plot a single parametric function. You can either specify the points as x and y, or giving a single complex number.

## Parametric Plots

Parametric plotting tab in the Create Plot window.

Here is an example of a parametric plot. Similar operations can be done on such graphs as can be done on the other line plots.

##

Parametric plot produced

For plotting using the command line see the documentation of the LinePlotParametric or LinePlotCParametric function.

# Surface Plots

&appname; can also plot surfaces. Select the "Surface plot" tab in the main notebook of the Create Plot window. Here you can specify a single expression which should use either x and y as real independent variables or z as a complex variable (where x is the real part of z and y is the imaginary part). For example to plot the modulus of the cosine function for complex parameters, you could enter `|cos(z)|`. This would be equivalent to `|cos(x+1i*y)|`.

## Surface plot

Modulus of the complex cosine function.

For plotting using the command line see the documentation of the SurfacePlot function.