@@ -403,12 +403,53 @@ def _makefill(self, x, y, kw, kwargs):
403403return seg ,kwargs
404404
405405def _plot_args (self ,tup ,kwargs ,return_kwargs = False ):
406+ """
407+ Process the arguments of ``plot([x], y, [fmt], **kwargs)`` calls.
408+
409+ This processes a single set of ([x], y, [fmt]) parameters; i.e. for
410+ ``plot(x, y, x2, y2)`` it will be called twice. Once for (x, y) and
411+ once for (x2, y2).
412+
413+ x and y may be 2D and thus can still represent multiple datasets.
414+
415+ For multiple datasets, if the keyword argument *label* is a list, this
416+ will unpack the list and assign the individual labels to the datasets.
417+
418+ Parameters
419+ ----------
420+ tup : tuple
421+ A tuple of the positional parameters. This can be one of
422+
423+ - (y,)
424+ - (x, y)
425+ - (y, fmt)
426+ - (x, y, fmt)
427+
428+ kwargs : dict
429+ The keyword arguments passed to ``plot()``.
430+
431+ return_kwargs : bool
432+ If true, return the effective keyword arguments after label
433+ unpacking as well.
434+
435+ Returns
436+ -------
437+ result
438+ If *return_kwargs* is false, a list of Artists representing the
439+ dataset(s).
440+ If *return_kwargs* is true, a list of (Artist, effective_kwargs)
441+ representing the dataset(s). See *return_kwargs*.
442+ The Artist is either `.Line2D` (if called from ``plot()``) or
443+ `.Polygon` otherwise.
444+ """
406445if len (tup )> 1 and isinstance (tup [- 1 ],str ):
407- linestyle ,marker ,color = _process_plot_format (tup [- 1 ])
408- tup = tup [:- 1 ]
446+ # xy is tup with fmt stripped (could still be (y,) only)
447+ * xy ,fmt = tup
448+ linestyle ,marker ,color = _process_plot_format (fmt )
409449elif len (tup )== 3 :
410450raise ValueError ('third arg must be a format string' )
411451else :
452+ xy = tup
412453linestyle ,marker ,color = None ,None ,None
413454
414455# Don't allow any None value; these would be up-converted to one
@@ -417,16 +458,16 @@ def _plot_args(self, tup, kwargs, return_kwargs=False):
417458raise ValueError ("x, y, and format string must not be None" )
418459
419460kw = {}
420- for k ,v in zip (('linestyle' ,'marker' ,'color' ),
421- (linestyle ,marker ,color )):
461+ for prop_name ,v in zip (('linestyle' ,'marker' ,'color' ),
462+ linestyle ,marker ,color )):
422463if v is not None :
423- kw [k ]= v
464+ kw [prop_name ]= v
424465
425- if len (tup )== 2 :
426- x = _check_1d (tup [0 ])
427- y = _check_1d (tup [ - 1 ])
466+ if len (xy )== 2 :
467+ x = _check_1d (xy [0 ])
468+ y = _check_1d (xy [ 1 ])
428469else :
429- x ,y = index_of (tup [- 1 ])
470+ x ,y = index_of (xy [- 1 ])
430471
431472if self .axes .xaxis is not None :
432473self .axes .xaxis .update_units (x )
@@ -445,10 +486,10 @@ def _plot_args(self, tup, kwargs, return_kwargs=False):
445486y = y [:,np .newaxis ]
446487
447488if self .command == 'plot' :
448- func = self ._makeline
489+ make_artist = self ._makeline
449490else :
450491kw ['closed' ]= kwargs .get ('closed' ,True )
451- func = self ._makefill
492+ make_artist = self ._makefill
452493
453494ncx ,ncy = x .shape [1 ],y .shape [1 ]
454495if ncx > 1 and ncy > 1 and ncx != ncy :
@@ -465,8 +506,8 @@ def _plot_args(self, tup, kwargs, return_kwargs=False):
465506else :
466507labels = [label ]* n_datasets
467508
468- result = (func (x [:,j % ncx ],y [:,j % ncy ],kw ,
469- {** kwargs ,'label' :label })
509+ result = (make_artist (x [:,j % ncx ],y [:,j % ncy ],kw ,
510+ ** kwargs ,'label' :label })
470511for j ,label in enumerate (labels ))
471512
472513if return_kwargs :