Canvas is an object that corresponds to a single output file. It
provides a set of methods for drawing lines, polygons, texts, and other
things in a manner independent of the file's format. Canvas is usually
hidden from the user, as PyChart creates a default canvas when it
starts up and implicitly writes all charts on the default canvas (unless
the user specifies otherwise; more on that later). There are some
occasions, however, in which you might want to manipulate a canvas
explicitly, e.g., when you want to create multiple plots from a single
file, or you just want to add lines and texts directly.
Class canvas.T
is an abstract base class. PyChart provides several
subclasses that correspond to specific file formats. For example,
pscanvas.T
implements methods for PostScript output. Class
pdfcanvas.T
implements methods for PDF output.
format