Merge pull request #14750 from anntzer/appendless

efiring · web-flow · commit bfda3a478342 · 2019-07-16T18:00:27.000-10:00
Misc. simplifications.
diff --git a/examples/event_handling/pipong.py b/examples/event_handling/pipong.py
@@ -169,9 +169,8 @@ def __init__(self, ax):
         self.on = False
         self.inst = True    # show instructions from the beginning
         self.background = None
-        self.pads = []
-        self.pads.append(Pad(pA, padAx, padAy))
-        self.pads.append(Pad(pB, padBx, padBy, 'r'))
+        self.pads = [Pad(pA, padAx, padAy),
+                     Pad(pB, padBx, padBy, 'r')]
         self.pucks = []
         self.i = self.ax.annotate(instructions, (.5, 0.5),
                                   name='monospace',
diff --git a/examples/statistics/errorbars_and_boxes.py b/examples/statistics/errorbars_and_boxes.py
@@ -42,13 +42,9 @@
 def make_error_boxes(ax, xdata, ydata, xerror, yerror, facecolor='r',
                      edgecolor='None', alpha=0.5):
 
-    # Create list for all the error patches
-    errorboxes = []
-
     # Loop over data points; create box from errors at each point
-    for x, y, xe, ye in zip(xdata, ydata, xerror.T, yerror.T):
-        rect = Rectangle((x - xe[0], y - ye[0]), xe.sum(), ye.sum())
-        errorboxes.append(rect)
+    errorboxes = [Rectangle((x - xe[0], y - ye[0]), xe.sum(), ye.sum())
+                  for x, y, xe, ye in zip(xdata, ydata, xerror.T, yerror.T)]
 
     # Create patch collection with specified colour/alpha
     pc = PatchCollection(errorboxes, facecolor=facecolor, alpha=alpha,
diff --git a/examples/units/evans_test.py b/examples/units/evans_test.py
@@ -69,14 +69,10 @@ def default_units(x, axis):
 units.registry[Foo] = FooConverter()
 
 # create some Foos
-x = []
-for val in range(0, 50, 2):
-    x.append(Foo(val, 1.0))
-
+x = [Foo(val, 1.0) for val in range(0, 50, 2)]
 # and some arbitrary y data
 y = [i for i in range(len(x))]
 
-
 fig, (ax1, ax2) = plt.subplots(1, 2)
 fig.suptitle("Custom units")
 fig.subplots_adjust(bottom=0.2)
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -5056,11 +5056,9 @@ def fill(self, *args, data=None, **kwargs):
         """
         # For compatibility(!), get aliases from Line2D rather than Patch.
         kwargs = cbook.normalize_kwargs(kwargs, mlines.Line2D)
-
-        patches = []
-        for poly in self._get_patches_for_fill(*args, data=data, **kwargs):
+        patches = [*self._get_patches_for_fill(*args, data=data, **kwargs)]
+        for poly in patches:
             self.add_patch(poly)
-            patches.append(poly)
         self._request_autoscale_view()
         return patches
 
diff --git a/lib/matplotlib/axes/_base.py b/lib/matplotlib/axes/_base.py
@@ -308,7 +308,6 @@ def _makefill(self, x, y, kw, kwargs):
         return seg
 
     def _plot_args(self, tup, kwargs):
-        ret = []
         if len(tup) > 1 and isinstance(tup[-1], str):
             linestyle, marker, color = _process_plot_format(tup[-1])
             tup = tup[:-1]
@@ -361,10 +360,8 @@ def _plot_args(self, tup, kwargs):
             cbook.warn_deprecated(
                 "2.2", message="cycling among columns of inputs with "
                 "non-matching shapes is deprecated.")
-        for j in range(max(ncx, ncy)):
-            seg = func(x[:, j % ncx], y[:, j % ncy], kw, kwargs)
-            ret.append(seg)
-        return ret
+        return [func(x[:, j % ncx], y[:, j % ncy], kw, kwargs)
+                for j in range(max(ncx, ncy))]
 
 
 class _AxesBase(martist.Artist):
diff --git a/lib/matplotlib/backend_tools.py b/lib/matplotlib/backend_tools.py
@@ -1051,13 +1051,9 @@ def _format_tool_keymap(self, name):
         return ", ".join(self.format_shortcut(keymap) for keymap in keymaps)
 
     def _get_help_entries(self):
-        entries = []
-        for name, tool in sorted(self.toolmanager.tools.items()):
-            if not tool.description:
-                continue
-            entries.append((name, self._format_tool_keymap(name),
-                            tool.description))
-        return entries
+        return [(name, self._format_tool_keymap(name), tool.description)
+                for name, tool in sorted(self.toolmanager.tools.items())
+                if tool.description]
 
     def _get_help_text(self):
         entries = self._get_help_entries()
diff --git a/lib/matplotlib/backends/backend_pgf.py b/lib/matplotlib/backends/backend_pgf.py
@@ -687,7 +687,7 @@ def draw_text(self, gc, x, y, s, prop, angle, ismath=False, mtext=None):
         writeln(self.fh, r"\pgfsetfillcolor{textcolor}")
         s = r"\color{textcolor}" + s
 
-        f = 1.0 / self.figure.dpi
+        dpi = self.figure.dpi
         text_args = []
         if mtext and (
                 (angle == 0 or
@@ -697,20 +697,18 @@ def draw_text(self, gc, x, y, s, prop, angle, ismath=False, mtext=None):
             # and add alignment information
             pos = mtext.get_unitless_position()
             x, y = mtext.get_transform().transform(pos)
-            text_args.append("x=%fin" % (x * f))
-            text_args.append("y=%fin" % (y * f))
-
             halign = {"left": "left", "right": "right", "center": ""}
             valign = {"top": "top", "bottom": "bottom",
                       "baseline": "base", "center": ""}
-            text_args.append(halign[mtext.get_horizontalalignment()])
-            text_args.append(valign[mtext.get_verticalalignment()])
+            text_args.extend([
+                f"x={x/dpi}in",
+                f"y={y/dpi}in",
+                halign[mtext.get_horizontalalignment()],
+                valign[mtext.get_verticalalignment()],
+            ])
         else:
-            # if not, use the text layout provided by matplotlib
-            text_args.append("x=%fin" % (x * f))
-            text_args.append("y=%fin" % (y * f))
-            text_args.append("left")
-            text_args.append("base")
+            # if not, use the text layout provided by Matplotlib.
+            text_args.append(f"x={x/dpi}in, y={y/dpi}in, left, base")
 
         if angle != 0:
             text_args.append("rotate=%f" % angle)
diff --git a/lib/matplotlib/table.py b/lib/matplotlib/table.py
@@ -227,16 +227,11 @@ def visible_edges(self, value):
     def get_path(self):
         """Return a `.Path` for the `.visible_edges`."""
         codes = [Path.MOVETO]
-
-        for edge in self._edges:
-            if edge in self._visible_edges:
-                codes.append(Path.LINETO)
-            else:
-                codes.append(Path.MOVETO)
-
+        codes.extend(
+            Path.LINETO if edge in self._visible_edges else Path.MOVETO
+            for edge in self._edges)
         if Path.MOVETO not in codes[1:]:  # All sides are visible
             codes[-1] = Path.CLOSEPOLY
-
         return Path(
             [[0.0, 0.0], [1.0, 0.0], [1.0, 1.0], [0.0, 1.0], [0.0, 0.0]],
             codes,
diff --git a/lib/matplotlib/testing/jpl_units/StrConverter.py b/lib/matplotlib/testing/jpl_units/StrConverter.py
@@ -79,11 +79,7 @@ def convert(value, unit, axis):
             if v not in labels and v not in newValues:
                 newValues.append(v)
 
-        for v in newValues:
-            if labels:
-                labels.append(v)
-            else:
-                labels = [v]
+        labels.extend(newValues)
 
         # DISABLED: This is disabled because matplotlib bar plots do not
         # DISABLED: recalculate the unit conversion of the data values
@@ -113,14 +109,7 @@ def convert(value, unit, axis):
         else:
             ax.set_ylim(ticks[0], ticks[-1])
 
-        result = []
-        for v in value:
-            # If v is not in labels then something went wrong with adding new
-            # labels to the list of old labels.
-            errmsg = "This is due to a logic error in the StrConverter class."
-            errmsg += " Please report this error and its message in bugzilla."
-            assert v in labels, errmsg
-            result.append(ticks[labels.index(v)])
+        result = [ticks[labels.index(v)] for v in value]
 
         ax.viewLim.ignore(-1)
         return result
diff --git a/lib/matplotlib/tests/test_mathtext.py b/lib/matplotlib/tests/test_mathtext.py
@@ -145,15 +145,14 @@
 
 font_tests = []
 for fonts, chars in font_test_specs:
-    wrapper = [' '.join(fonts), ' $']
-    for font in fonts:
-        wrapper.append(r'\%s{' % font)
-    wrapper.append('%s')
-    for font in fonts:
-        wrapper.append('}')
-    wrapper.append('$')
-    wrapper = ''.join(wrapper)
-
+    wrapper = ''.join([
+        ' '.join(fonts),
+        ' $',
+        *(r'\%s{' % font for font in fonts),
+        '%s',
+        *('}' for font in fonts),
+        '$',
+    ])
     for set in chars:
         font_tests.append(wrapper % set)
 
diff --git a/lib/matplotlib/tight_layout.py b/lib/matplotlib/tight_layout.py
@@ -96,11 +96,9 @@ def auto_adjust_subplotpars(
     union = Bbox.union
 
     if ax_bbox_list is None:
-        ax_bbox_list = []
-        for subplots in subplot_list:
-            ax_bbox = union([ax.get_position(original=True)
-                             for ax in subplots])
-            ax_bbox_list.append(ax_bbox)
+        ax_bbox_list = [
+            union([ax.get_position(original=True) for ax in subplots])
+            for subplots in subplot_list]
 
     for subplots, ax_bbox, (num1, num2) in zip(subplot_list,
                                                ax_bbox_list,
diff --git a/lib/matplotlib/widgets.py b/lib/matplotlib/widgets.py
@@ -9,6 +9,7 @@
 wide and tall you want your Axes to be to accommodate your widget.
 """
 
+from contextlib import ExitStack
 import copy
 from numbers import Integral
 
@@ -1194,26 +1195,16 @@ def __init__(self, targetfig, toolfig):
                    self.slidertop, self.sliderwspace, self.sliderhspace,)
 
         def func(event):
-            thisdrawon = self.drawon
-
-            self.drawon = False
-
-            # store the drawon state of each slider
-            bs = []
-            for slider in sliders:
-                bs.append(slider.drawon)
-                slider.drawon = False
-
-            # reset the slider to the initial position
-            for slider in sliders:
-                slider.reset()
-
-            # reset drawon
-            for slider, b in zip(sliders, bs):
-                slider.drawon = b
-
-            # draw the canvas
-            self.drawon = thisdrawon
+            with ExitStack() as stack:
+                # Temporarily disable drawing on self and self's sliders.
+                stack.enter_context(cbook._setattr_cm(self, drawon=False))
+                for slider in sliders:
+                    stack.enter_context(
+                        cbook._setattr_cm(slider, drawon=False))
+                # Reset the slider to the initial position.
+                for slider in sliders:
+                    slider.reset()
+            # Draw the canvas.
             if self.drawon:
                 toolfig.canvas.draw()
                 self.targetfig.canvas.draw()
diff --git a/lib/mpl_toolkits/axes_grid1/axes_divider.py b/lib/mpl_toolkits/axes_grid1/axes_divider.py
@@ -91,14 +91,9 @@ def _calc_k(l, total_size):
 
     @staticmethod
     def _calc_offsets(l, k):
-
         offsets = [0.]
-
-        #for s in l:
         for _rs, _as in l:
-            #_rs, _as = s.get_size(renderer)
             offsets.append(offsets[-1] + _rs*k + _as)
-
         return offsets
 
     def set_position(self, pos):
@@ -703,11 +698,8 @@ def _determine_karray(equivalent_sizes, appended_sizes,
     @staticmethod
     def _calc_offsets(appended_sizes, karray):
         offsets = [0.]
-
-        #for s in l:
         for (r, a), k in zip(appended_sizes, karray):
             offsets.append(offsets[-1] + r*k + a)
-
         return offsets
 
     def new_locator(self, nx, nx1=None):
diff --git a/lib/mpl_toolkits/mplot3d/art3d.py b/lib/mpl_toolkits/mplot3d/art3d.py
@@ -627,25 +627,15 @@ def set_zsort(self, zsort):
 
     def get_vector(self, segments3d):
         """Optimize points for projection."""
-        si = 0
-        ei = 0
-        segis = []
-        points = []
-        for p in segments3d:
-            points.extend(p)
-            ei = si + len(p)
-            segis.append((si, ei))
-            si = ei
-
         if len(segments3d):
-            xs, ys, zs = zip(*points)
-        else:
-            # We need this so that we can skip the bad unpacking from zip()
+            xs, ys, zs = np.row_stack(segments3d).T
+        else:  # row_stack can't stack zero arrays.
             xs, ys, zs = [], [], []
-
         ones = np.ones(len(xs))
         self._vec = np.array([xs, ys, zs, ones])
-        self._segis = segis
+
+        indices = [0, *np.cumsum([len(segment) for segment in segments3d])]
+        self._segslices = [*map(slice, indices[:-1], indices[1:])]
 
     def set_verts(self, verts, closed=True):
         """Set 3D vertices."""
@@ -688,8 +678,7 @@ def do_3d_projection(self, renderer):
             self._facecolors3d = self._facecolors
 
         txs, tys, tzs = proj3d._proj_transform_vec(self._vec, renderer.M)
-        xyzlist = [(txs[si:ei], tys[si:ei], tzs[si:ei])
-                   for si, ei in self._segis]
+        xyzlist = [(txs[sl], tys[sl], tzs[sl]) for sl in self._segslices]
 
         # This extra fuss is to re-order face / edge colors
         cface = self._facecolors3d
