def stem(self, x, y, linefmt='<STR_LIT>', markerfmt='<STR_LIT>', basefmt='<STR_LIT>'):
remember_hold=self._hold<EOL>if not self._hold: self.cla()<EOL>self.hold(True)<EOL>markerline, = self.plot(x, y, markerfmt)<EOL>stemlines = []<EOL>for thisx, thisy in zip(x, y):<EOL><INDENT>l, = self.plot([thisx,thisx], [<NUM_LIT:0>, thisy], linefmt)<EOL>stemlines.append(l)<EOL><DEDENT>baseline, = self.plot([np.amin(x), np.amax(x)], [<NUM_LIT:0>,<NUM_LIT:0>], basefmt)<EOL>self.hold(remember_hold)<EOL>return markerline, stemlines, baseline<EOL>
call signature::

  stem(x, y, linefmt='b-', markerfmt='bo', basefmt='r-')

A stem plot plots vertical lines (using *linefmt*) at each *x*
location from the baseline to *y*, and places a marker there
using *markerfmt*.  A horizontal line at 0 is is plotted using
*basefmt*.

Return value is a tuple (*markerline*, *stemlines*,
*baseline*).

.. seealso::
    `this document`__ for details

    :file:`examples/pylab_examples/stem_plot.py`:
        for a demo

__ http://www.mathworks.com/access/helpdesk/help/techdoc/ref/stem.html