Node:Anatomy,
Next:Attributes,
Previous:Options,
Up:Top
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 below picture shows example of a chart and its components.
The standard set of component classes follow:
- area.T
- This 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.
- bar_plot.T
- line_plot.T
- pie_plot.T
- range_plot.T
- interval_plot.T
- These classes actually plot a chart. 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 class draws an optional rectangular box that describes what each plot
means (see legend).
- text_box.T
- This class draws 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.