MATLAB provides a great variety of functions
and techniques for graphical display of data. The flexibility and
ease of use of MATLAB's plotting tools is one of its key strengths.
In MATLAB graphs are shown in a figure window. Several figure
windows can be displayed simultaneously, but only one is active.
All graphing commands are applied to the active figure. The command
`figure(n)`

will activate figure number
`n`

or create a new figure indexed by
`n`

.