matplotlib · tacaswell · May 28, 2019 · May 28, 2019
diff --git a/lib/matplotlib/animation.py b/lib/matplotlib/animation.py
@@ -806,16 +806,15 @@ def __init__(self, fps=30, codec=None, bitrate=None, extra_args=None,
         # Convert from MB to bytes
         self._bytes_limit *= 1024 * 1024
 
-        if self.default_mode not in ['loop', 'once', 'reflect']:
-            raise ValueError(
-                "unrecognized default_mode {!r}".format(self.default_mode))
+        cbook._check_in_list(['loop', 'once', 'reflect'],
+                             default_mode=self.default_mode)
 
         super().__init__(fps, codec, bitrate, extra_args, metadata)
 
     def setup(self, fig, outfile, dpi, frame_dir=None):
         outfile = Path(outfile)
-        if outfile.suffix not in ['.html', '.htm']:
-            raise ValueError("outfile must be *.htm or *.html")
+        cbook._check_in_list(['.html', '.htm'],
+                             outfile_extension=outfile.suffix)
 
         self._saved_frames = []
         self._total_bytes = 0

diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -138,12 +138,11 @@ def get_title(self, loc="center"):
             The title text string.
 
         """
-        try:
-            title = {'left': self._left_title,
-                     'center': self.title,
-                     'right': self._right_title}[loc.lower()]
-        except KeyError:
-            raise ValueError("'%s' is not a valid location" % loc)
+        titles = {'left': self._left_title,
+                  'center': self.title,
+                  'right': self._right_title}
+        cbook._check_in_list(titles, loc=loc.lower())
+        title = titles[loc.lower()]
         return title.get_text()
 
     def set_title(self, label, fontdict=None, loc=None, pad=None,
@@ -188,15 +187,14 @@ def set_title(self, label, fontdict=None, loc=None, pad=None,
             :class:`~matplotlib.text.Text` for a list of valid text
             properties.
         """
-        try:
-            if loc is None:
-                loc = rcParams['axes.titlelocation']
-
-            title = {'left': self._left_title,
-                     'center': self.title,
-                     'right': self._right_title}[loc.lower()]
-        except KeyError:
-            raise ValueError("'%s' is not a valid location" % loc)
+        if loc is None:
+            loc = rcParams['axes.titlelocation']
+
+        titles = {'left': self._left_title,
+                  'center': self.title,
+                  'right': self._right_title}
+        cbook._check_in_list(titles, loc=loc.lower())
+        title = titles[loc.lower()]
         default = {
             'fontsize': rcParams['axes.titlesize'],
             'fontweight': rcParams['axes.titleweight'],
@@ -2098,9 +2096,7 @@ def step(self, x, y, *args, where='pre', data=None, **kwargs):
         -----
         .. [notes section required to get data note injection right]
         """
-        if where not in ('pre', 'post', 'mid'):
-            raise ValueError("'where' argument to step must be "
-                             "'pre', 'post' or 'mid'")
+        cbook._check_in_list(('pre', 'post', 'mid'), where=where)
         kwargs['drawstyle'] = 'steps-' + where
         return self.plot(x, y, *args, data=data, **kwargs)
 
@@ -2293,6 +2289,8 @@ def bar(self, x, height, width=0.8, bottom=None, *, align="center",
         error_kw.setdefault('capsize', capsize)
 
         orientation = kwargs.pop('orientation', 'vertical')
+        cbook._check_in_list(['vertical', 'horizontal'],
+                             orientation=orientation)
         log = kwargs.pop('log', False)
         label = kwargs.pop('label', '')
         tick_labels = kwargs.pop('tick_label', None)
@@ -2321,8 +2319,6 @@ def bar(self, x, height, width=0.8, bottom=None, *, align="center",
             self._process_unit_info(xdata=width, ydata=y, kwargs=kwargs)
             if log:
                 self.set_xscale('log', nonposx='clip')
-        else:
-            raise ValueError('invalid orientation: %s' % orientation)
 
         # lets do some conversions now since some types cannot be
         # subtracted uniformly
@@ -2365,6 +2361,7 @@ def bar(self, x, height, width=0.8, bottom=None, *, align="center",
 
         # We will now resolve the alignment and really have
         # left, bottom, width, height vectors
+        cbook._check_in_list(['center', 'edge'], align=align)
         if align == 'center':
             if orientation == 'vertical':
                 try:
@@ -2385,8 +2382,6 @@ def bar(self, x, height, width=0.8, bottom=None, *, align="center",
         elif align == 'edge':
             left = x
             bottom = y
-        else:
-            raise ValueError('invalid alignment: %s' % align)
 
         patches = []
         args = zip(left, bottom, width, height, color, edgecolor, linewidth)

diff --git a/lib/matplotlib/backends/backend_cairo.py b/lib/matplotlib/backends/backend_cairo.py
@@ -338,11 +338,9 @@ def set_alpha(self, alpha):
         # one for False.
 
     def set_capstyle(self, cs):
-        if cs in ('butt', 'round', 'projecting'):
-            self._capstyle = cs
-            self.ctx.set_line_cap(self._capd[cs])
-        else:
-            raise ValueError('Unrecognized cap style.  Found %s' % cs)
+        cbook._check_in_list(('butt', 'round', 'projecting'), capstyle=cs)
+        self._capstyle = cs
+        self.ctx.set_line_cap(self._capd[cs])
 
     def set_clip_rectangle(self, rectangle):
         if not rectangle:
@@ -384,11 +382,9 @@ def get_rgb(self):
         return self.ctx.get_source().get_rgba()[:3]
 
     def set_joinstyle(self, js):
-        if js in ('miter', 'round', 'bevel'):
-            self._joinstyle = js
-            self.ctx.set_line_join(self._joind[js])
-        else:
-            raise ValueError('Unrecognized join style.  Found %s' % js)
+        cbook._check_in_list(('miter', 'round', 'bevel'), joinstyle=js)
+        self._joinstyle = js
+        self.ctx.set_line_join(self._joind[js])
 
     def set_linewidth(self, w):
         self._linewidth = float(w)

diff --git a/lib/matplotlib/collections.py b/lib/matplotlib/collections.py
@@ -559,10 +559,8 @@ def set_capstyle(self, cs):
         cs : {'butt', 'round', 'projecting'}
             The capstyle
         """
-        if cs in ('butt', 'round', 'projecting'):
-            self._capstyle = cs
-        else:
-            raise ValueError('Unrecognized cap style.  Found %s' % cs)
+        cbook._check_in_list(('butt', 'round', 'projecting'), capstyle=cs)
+        self._capstyle = cs
 
     def get_capstyle(self):
         return self._capstyle
@@ -576,10 +574,8 @@ def set_joinstyle(self, js):
         js : {'miter', 'round', 'bevel'}
             The joinstyle
         """
-        if js in ('miter', 'round', 'bevel'):
-            self._joinstyle = js
-        else:
-            raise ValueError('Unrecognized join style.  Found %s' % js)
+        cbook._check_in_list(('miter', 'round', 'bevel'), joinstyle=js)
+        self._joinstyle = js
 
     def get_joinstyle(self):
         return self._joinstyle

diff --git a/lib/matplotlib/colorbar.py b/lib/matplotlib/colorbar.py
@@ -977,12 +977,9 @@ def _get_extension_lengths(self, frac, automin, automax, default=0.05):
         # Set the default value.
         extendlength = np.array([default, default])
         if isinstance(frac, str):
-            if frac.lower() == 'auto':
-                # Use the provided values when 'auto' is required.
-                extendlength[:] = [automin, automax]
-            else:
-                # Any other string is invalid.
-                raise ValueError('invalid value for extendfrac')
+            cbook._check_in_list(['auto'], extendfrac=frac.lower())
+            # Use the provided values when 'auto' is required.
+            extendlength[:] = [automin, automax]
         elif frac is not None:
             try:
                 # Try to set min and max extension fractions directly.
@@ -1351,9 +1348,7 @@ def make_axes(parents, location=None, orientation=None, fraction=0.15,
     if location is None:
         location = 'right' if orientation == 'vertical' else 'bottom'
 
-    if location not in locations:
-        raise ValueError('Invalid colorbar location. Must be one '
-                         'of %s' % ', '.join(locations))
+    cbook._check_in_list(locations, location=location)
 
     default_location_settings = {'left':   {'anchor': (1.0, 0.5),
                                             'panchor': (0.0, 0.5),

diff --git a/lib/matplotlib/image.py b/lib/matplotlib/image.py
@@ -717,8 +717,7 @@ def set_interpolation(self, s):
         if s is None:
             s = rcParams['image.interpolation']
         s = s.lower()
-        if s not in _interpd_:
-            raise ValueError('Illegal interpolation string')
+        cbook._check_in_list(_interpd_, interpolation=s)
         self._interpolation = s
         self.stale = True
 

diff --git a/lib/matplotlib/legend.py b/lib/matplotlib/legend.py
@@ -63,11 +63,8 @@ def __init__(self, legend, use_blit=False, update="loc"):
         """
         self.legend = legend
 
-        if update in ["loc", "bbox"]:
-            self._update = update
-        else:
-            raise ValueError("update parameter '%s' is not supported." %
-                             update)
+        cbook._check_in_list(["loc", "bbox"], update=update)
+        self._update = update
 
         DraggableOffsetBox.__init__(self, legend, legend._legend_box,
                                     use_blit=use_blit)

diff --git a/lib/matplotlib/mlab.py b/lib/matplotlib/mlab.py
@@ -466,10 +466,9 @@ def _spectral_helper(x, y=None, NFFT=None, Fs=None, detrend_func=None,
 
     if mode is None or mode == 'default':
         mode = 'psd'
-    elif mode not in ['psd', 'complex', 'magnitude', 'angle', 'phase']:
-        raise ValueError("Unknown value for mode %s, must be one of: "
-                         "'default', 'psd', 'complex', "
-                         "'magnitude', 'angle', 'phase'" % mode)
+    cbook._check_in_list(
+        ['default', 'psd', 'complex', 'magnitude', 'angle', 'phase'],
+        mode=mode)
 
     if not same_data and mode != 'psd':
         raise ValueError("x and y must be equal if mode is not 'psd'")
@@ -485,9 +484,7 @@ def _spectral_helper(x, y=None, NFFT=None, Fs=None, detrend_func=None,
             sides = 'twosided'
         else:
             sides = 'onesided'
-    elif sides not in ['onesided', 'twosided']:
-        raise ValueError("Unknown value for sides %s, must be one of: "
-                         "'default', 'onesided', or 'twosided'" % sides)
+    cbook._check_in_list(['default', 'onesided', 'twosided'], sides=sides)
 
     # zero pad x and y up to NFFT if they are shorter than NFFT
     if len(x) < NFFT:
@@ -604,9 +601,7 @@ def _single_spectrum_helper(x, mode, Fs=None, window=None, pad_to=None,
     complex, magnitude, angle, and phase spectrums.
     It is *NOT* meant to be used outside of mlab and may change at any time.
     '''
-    if mode is None or mode == 'psd' or mode == 'default':
-        raise ValueError('_single_spectrum_helper does not work with %s mode'
-                         % mode)
+    cbook._check_in_list(['complex', 'magnitude', 'angle', 'phase'], mode=mode)
 
     if pad_to is None:
         pad_to = len(x)

diff --git a/lib/matplotlib/offsetbox.py b/lib/matplotlib/offsetbox.py
@@ -1019,12 +1019,8 @@ def __init__(self, loc,
         self.set_child(child)
 
         if isinstance(loc, str):
-            try:
-                loc = self.codes[loc]
-            except KeyError:
-                raise ValueError('Unrecognized location "%s". Valid '
-                                 'locations are\n\t%s\n'
-                                 % (loc, '\n\t'.join(self.codes)))
+            cbook._check_in_list(self.codes, loc=loc)
+            loc = self.codes[loc]
 
         self.loc = loc
         self.borderpad = borderpad

diff --git a/lib/matplotlib/patches.py b/lib/matplotlib/patches.py
@@ -422,9 +422,7 @@ def set_capstyle(self, s):
         s : {'butt', 'round', 'projecting'}
         """
         s = s.lower()
-        if s not in self.validCap:
-            raise ValueError('set_capstyle passed "%s";\n' % (s,) +
-                             'valid capstyles are %s' % (self.validCap,))
+        cbook._check_in_list(self.validCap, capstyle=s)
         self._capstyle = s
         self.stale = True
 
@@ -441,9 +439,7 @@ def set_joinstyle(self, s):
         s : {'miter', 'round', 'bevel'}
         """
         s = s.lower()
-        if s not in self.validJoin:
-            raise ValueError('set_joinstyle passed "%s";\n' % (s,) +
-                             'valid joinstyles are %s' % (self.validJoin,))
+        cbook._check_in_list(self.validJoin, joinstyle=s)
         self._joinstyle = s
         self.stale = True
 

diff --git a/lib/matplotlib/scale.py b/lib/matplotlib/scale.py
@@ -723,8 +723,7 @@ def scale_factory(scale, axis, **kwargs):
     axis : Axis
     """
     scale = scale.lower()
-    if scale not in _scale_mapping:
-        raise ValueError("Unknown scale type '%s'" % scale)
+    cbook._check_in_list(_scale_mapping, scale=scale)
     return _scale_mapping[scale](axis, **kwargs)
 
 if scale_factory.__doc__:

diff --git a/lib/matplotlib/stackplot.py b/lib/matplotlib/stackplot.py
@@ -8,6 +8,8 @@
 """
 import numpy as np
 
+import matplotlib.cbook as cbook
+
 __all__ = ['stackplot']
 
 
@@ -68,6 +70,8 @@ def stackplot(axes, x, *args,
     # We'll need a float buffer for the upcoming calculations.
     stack = np.cumsum(y, axis=0, dtype=np.promote_types(y.dtype, np.float32))
 
+    cbook._check_in_list(['zero', 'sym', 'wiggle', 'weighted_wiggle'],
+                         baseline=baseline)
     if baseline == 'zero':
         first_line = 0.
 
@@ -97,11 +101,6 @@ def stackplot(axes, x, *args,
         first_line = center - 0.5 * total
         stack += first_line
 
-    else:
-        errstr = "Baseline method %s not recognised. " % baseline
-        errstr += "Expected 'zero', 'sym', 'wiggle' or 'weighted_wiggle'"
-        raise ValueError(errstr)
-
     # Color between x = 0 and the first array.
     color = axes._get_lines.get_next_color()
     coll = axes.fill_between(x, first_line, stack[0, :],

diff --git a/lib/matplotlib/streamplot.py b/lib/matplotlib/streamplot.py
@@ -6,6 +6,7 @@
 import numpy as np
 
 import matplotlib
+import matplotlib.cbook as cbook
 import matplotlib.cm as cm
 import matplotlib.colors as mcolors
 import matplotlib.collections as mcollections
@@ -103,11 +104,8 @@ def streamplot(axes, x, y, u, v, density=1, linewidth=None, color=None,
     line_kw = {}
     arrow_kw = dict(arrowstyle=arrowstyle, mutation_scale=10 * arrowsize)
 
-    if integration_direction not in ['both', 'forward', 'backward']:
-        errstr = ("Integration direction '%s' not recognised. "
-                  "Expected 'both', 'forward' or 'backward'." %
-                  integration_direction)
-        raise ValueError(errstr)
+    cbook._check_in_list(['both', 'forward', 'backward'],
+                         integration_direction=integration_direction)
 
     if integration_direction == 'both':
         maxlength /= 2.

diff --git a/lib/matplotlib/text.py b/lib/matplotlib/text.py
@@ -247,10 +247,8 @@ def set_rotation_mode(self, m):
             aligned according to their horizontal and vertical alignments.  If
             ``"anchor"``, then alignment occurs before rotation.
         """
-        if m is None or m in ["anchor", "default"]:
-            self._rotation_mode = m
-        else:
-            raise ValueError("Unknown rotation_mode : %s" % repr(m))
+        cbook._check_in_list(["anchor", "default", None], rotation_mode=m)
+        self._rotation_mode = m
         self.stale = True
 
     def get_rotation_mode(self):

diff --git a/lib/matplotlib/ticker.py b/lib/matplotlib/ticker.py
@@ -1948,9 +1948,7 @@ def set_params(self, **kwargs):
             self._symmetric = kwargs.pop('symmetric')
         if 'prune' in kwargs:
             prune = kwargs.pop('prune')
-            if prune is not None and prune not in ['upper', 'lower', 'both']:
-                raise ValueError(
-                    "prune must be 'upper', 'lower', 'both', or None")
+            cbook._check_in_list(['upper', 'lower', 'both', None], prune=prune)
             self._prune = prune
         if 'min_n_ticks' in kwargs:
             self._min_n_ticks = max(1, kwargs.pop('min_n_ticks'))
@@ -2206,9 +2204,7 @@ def subs(self, subs):
         if subs is None:  # consistency with previous bad API
             self._subs = 'auto'
         elif isinstance(subs, str):
-            if subs not in ('all', 'auto'):
-                raise ValueError("A subs string must be 'all' or 'auto'; "
-                                 "found '%s'." % subs)
+            cbook._check_in_list(('all', 'auto'), subs=subs)
             self._subs = subs
         else:
             self._subs = np.asarray(subs, dtype=float)