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Anatomy of a chart

A chart comprises a set of components. Each component belongs to a certain class, from which an instance tailored for a particular chart is generated. The standard set of component classes follow:

area.T
The area class defines the size, the location, and the coordinate system (linear, logarithmic, etc) of a chart (see area). It also contains axes, plots, and legends, as described below. At least one Area must be created in any chart.
axis.X
axis.Y
The axis class defines the look of an axis. You can specify, for example, the interval and the style of tick marks and grid lines (see axis). PyChart provides two types of axes, axis.X and axis.Y, corresponding to horizontal and vertical axes.
plot.T
The plot class actually draws a chart. Several subclasses of plots are provided by PyChart, including line plots (see line_plot), range-fill plots (see range_plot), bar plots (see bar_plot), and pie plots (see pie_plot). You can draw multiple plots in a single chart, and most of the times you can even mix different types of plots, e.g., line plots and bar plots.
legend.T
The legend class is an optional rectangular box that describes what each plot means (see legend).
text_box.T
The text_box is an optional rectangular box that contains arbitrary text. It can also contain arrows (see text_box).
canvas.T
The canvas is a "virtual paper" that defines graph-drawing primitives, such as lines, rectangles, and texts. One canvas corresponds to one output file. Canvas is used by other components in the graph and is usually not manipulated by users directly. It's handy, however, if you want to draw a line/circle/text/etc, directly on the Postscript or PDF file. See canvas.