Merge pull request matplotlib#23038 from anntzer/e3

Factor out errorevery parsing for 2D and 3D errorbars.

Author: oscargus

lib/matplotlib/axes/_axes.py

@@ -3201,6 +3201,38 @@ def get_next_color():
         else:
             return slices, texts, autotexts
 
+    @staticmethod
+    def _errorevery_to_mask(x, errorevery):
+        """
+        Normalize `errorbar`'s *errorevery* to be a boolean mask for data *x*.
+
+        This function is split out to be usable both by 2D and 3D errorbars.
+        """
+        if isinstance(errorevery, Integral):
+            errorevery = (0, errorevery)
+        if isinstance(errorevery, tuple):
+            if (len(errorevery) == 2 and
+                    isinstance(errorevery[0], Integral) and
+                    isinstance(errorevery[1], Integral)):
+                errorevery = slice(errorevery[0], None, errorevery[1])
+            else:
+                raise ValueError(
+                    f'{errorevery=!r} is a not a tuple of two integers')
+        elif isinstance(errorevery, slice):
+            pass
+        elif not isinstance(errorevery, str) and np.iterable(errorevery):
+            try:
+                x[errorevery]  # fancy indexing
+            except (ValueError, IndexError) as err:
+                raise ValueError(
+                    f"{errorevery=!r} is iterable but not a valid NumPy fancy "
+                    "index to match 'xerr'/'yerr'") from err
+        else:
+            raise ValueError(f"{errorevery=!r} is not a recognized value")
+        everymask = np.zeros(len(x), bool)
+        everymask[errorevery] = True
+        return everymask
+
     @_preprocess_data(replace_names=["x", "y", "xerr", "yerr"],
                       label_namer="y")
     @_docstring.dedent_interpd
@@ -3375,32 +3407,7 @@ def _upcast_err(err):
         if len(x) != len(y):
             raise ValueError("'x' and 'y' must have the same size")
 
-        if isinstance(errorevery, Integral):
-            errorevery = (0, errorevery)
-        if isinstance(errorevery, tuple):
-            if (len(errorevery) == 2 and
-                    isinstance(errorevery[0], Integral) and
-                    isinstance(errorevery[1], Integral)):
-                errorevery = slice(errorevery[0], None, errorevery[1])
-            else:
-                raise ValueError(
-                    f'errorevery={errorevery!r} is a not a tuple of two '
-                    f'integers')
-        elif isinstance(errorevery, slice):
-            pass
-        elif not isinstance(errorevery, str) and np.iterable(errorevery):
-            # fancy indexing
-            try:
-                x[errorevery]
-            except (ValueError, IndexError) as err:
-                raise ValueError(
-                    f"errorevery={errorevery!r} is iterable but not a valid "
-                    f"NumPy fancy index to match 'xerr'/'yerr'") from err
-        else:
-            raise ValueError(
-                f"errorevery={errorevery!r} is not a recognized value")
-        everymask = np.zeros(len(x), bool)
-        everymask[errorevery] = True
+        everymask = self._errorevery_to_mask(x, errorevery)
 
         label = kwargs.pop("label", None)
         kwargs['label'] = '_nolegend_'

lib/mpl_toolkits/mplot3d/axes3d.py

@@ -14,7 +14,6 @@
 import functools
 import itertools
 import math
-from numbers import Integral
 import textwrap
 
 import numpy as np
@@ -2899,33 +2898,7 @@ def errorbar(self, x, y, z, zerr=None, yerr=None, xerr=None, fmt='',
         if not len(x) == len(y) == len(z):
             raise ValueError("'x', 'y', and 'z' must have the same size")
 
-        if isinstance(errorevery, Integral):
-            errorevery = (0, errorevery)
-        if isinstance(errorevery, tuple):
-            if (len(errorevery) == 2 and
-                    isinstance(errorevery[0], Integral) and
-                    isinstance(errorevery[1], Integral)):
-                errorevery = slice(errorevery[0], None, errorevery[1])
-            else:
-                raise ValueError(
-                    f'errorevery={errorevery!r} is a not a tuple of two '
-                    f'integers')
-
-        elif isinstance(errorevery, slice):
-            pass
-
-        elif not isinstance(errorevery, str) and np.iterable(errorevery):
-            # fancy indexing
-            try:
-                x[errorevery]
-            except (ValueError, IndexError) as err:
-                raise ValueError(
-                    f"errorevery={errorevery!r} is iterable but not a valid "
-                    f"NumPy fancy index to match "
-                    f"'xerr'/'yerr'/'zerr'") from err
-        else:
-            raise ValueError(
-                f"errorevery={errorevery!r} is not a recognized value")
+        everymask = self._errorevery_to_mask(x, errorevery)
 
         label = kwargs.pop("label", None)
         kwargs['label'] = '_nolegend_'
@@ -2987,9 +2960,6 @@ def errorbar(self, x, y, z, zerr=None, yerr=None, xerr=None, fmt='',
             eb_cap_style['markeredgewidth'] = capthick
         eb_cap_style['color'] = ecolor
 
-        everymask = np.zeros(len(x), bool)
-        everymask[errorevery] = True
-
         def _apply_mask(arrays, mask):
             # Return, for each array in *arrays*, the elements for which *mask*
             # is True, without using fancy indexing.