Merge pull request matplotlib#27972 from anntzer/gn

Fix ngrids support in axes_grid.Grid().

Author: timhoffm

doc/api/next_api_changes/deprecations/27972-AL.rst

@@ -0,0 +1,8 @@
+``axes_grid.Grid.ngrids``
+~~~~~~~~~~~~~~~~~~~~~~~~~
+This attribute has been deprecated and renamed ``n_axes``, consistently with
+the new name of the `~.axes_grid.Grid` constructor parameter that allows
+setting the actual number of axes in the grid (the old parameter, ``ngrids``,
+did not actually work since Matplotlib 3.3).
+
+The same change has been made in ``axes_grid.ImageGrid``.

lib/mpl_toolkits/axes_grid1/axes_grid.py

@@ -51,16 +51,17 @@ class Grid:
         in the usage pattern ``grid.axes_row[row][col]``.
     axes_llc : Axes
         The Axes in the lower left corner.
-    ngrids : int
+    n_axes : int
         Number of Axes in the grid.
     """
 
     _defaultAxesClass = Axes
 
+    @_api.rename_parameter("3.11", "ngrids", "n_axes")
     def __init__(self, fig,
                  rect,
                  nrows_ncols,
-                 ngrids=None,
+                 n_axes=None,
                  direction="row",
                  axes_pad=0.02,
                  *,
@@ -83,8 +84,8 @@ def __init__(self, fig,
             ``121``), or as a `~.SubplotSpec`.
         nrows_ncols : (int, int)
             Number of rows and columns in the grid.
-        ngrids : int or None, default: None
-            If not None, only the first *ngrids* axes in the grid are created.
+        n_axes : int or None, default: None
+            If not None, only the first *n_axes* axes in the grid are created.
         direction : {"row", "column"}, default: "row"
             Whether axes are created in row-major ("row by row") or
             column-major order ("column by column").  This also affects the
@@ -116,14 +117,12 @@ def __init__(self, fig,
         """
         self._nrows, self._ncols = nrows_ncols
 
-        if ngrids is None:
-            ngrids = self._nrows * self._ncols
+        if n_axes is None:
+            n_axes = self._nrows * self._ncols
         else:
-            if not 0 < ngrids <= self._nrows * self._ncols:
+            if not 0 < n_axes <= self._nrows * self._ncols:
                 raise ValueError(
-                    "ngrids must be positive and not larger than nrows*ncols")
-
-        self.ngrids = ngrids
+                    "n_axes must be positive and not larger than nrows*ncols")
 
         self._horiz_pad_size, self._vert_pad_size = map(
             Size.Fixed, np.broadcast_to(axes_pad, 2))
@@ -150,7 +149,7 @@ def __init__(self, fig,
         rect = self._divider.get_position()
 
         axes_array = np.full((self._nrows, self._ncols), None, dtype=object)
-        for i in range(self.ngrids):
+        for i in range(n_axes):
             col, row = self._get_col_row(i)
             if share_all:
                 sharex = sharey = axes_array[0, 0]
@@ -160,9 +159,9 @@ def __init__(self, fig,
             axes_array[row, col] = axes_class(
                 fig, rect, sharex=sharex, sharey=sharey)
         self.axes_all = axes_array.ravel(
-            order="C" if self._direction == "row" else "F").tolist()
-        self.axes_column = axes_array.T.tolist()
-        self.axes_row = axes_array.tolist()
+            order="C" if self._direction == "row" else "F").tolist()[:n_axes]
+        self.axes_row = [[ax for ax in row if ax] for row in axes_array]
+        self.axes_column = [[ax for ax in col if ax] for col in axes_array.T]
         self.axes_llc = self.axes_column[0][-1]
 
         self._init_locators()
@@ -177,7 +176,7 @@ def _init_locators(self):
             [Size.Scaled(1), self._horiz_pad_size] * (self._ncols-1) + [Size.Scaled(1)])
         self._divider.set_vertical(
             [Size.Scaled(1), self._vert_pad_size] * (self._nrows-1) + [Size.Scaled(1)])
-        for i in range(self.ngrids):
+        for i in range(self.n_axes):
             col, row = self._get_col_row(i)
             self.axes_all[i].set_axes_locator(
                 self._divider.new_locator(nx=2 * col, ny=2 * (self._nrows - 1 - row)))
@@ -190,6 +189,9 @@ def _get_col_row(self, n):
 
         return col, row
 
+    n_axes = property(lambda self: len(self.axes_all))
+    ngrids = _api.deprecated(property(lambda self: len(self.axes_all)))
+
     # Good to propagate __len__ if we have __getitem__
     def __len__(self):
         return len(self.axes_all)
@@ -254,7 +256,10 @@ def set_label_mode(self, mode):
         if mode == "keep":
             return
         for i, j in np.ndindex(self._nrows, self._ncols):
-            ax = self.axes_row[i][j]
+            try:
+                ax = self.axes_row[i][j]
+            except IndexError:
+                continue
             if isinstance(ax.axis, MethodType):
                 bottom_axis = SimpleAxisArtist(ax.xaxis, 1, ax.spines["bottom"])
                 left_axis = SimpleAxisArtist(ax.yaxis, 1, ax.spines["left"])
@@ -293,7 +298,7 @@ class ImageGrid(Grid):
     def __init__(self, fig,
                  rect,
                  nrows_ncols,
-                 ngrids=None,
+                 n_axes=None,
                  direction="row",
                  axes_pad=0.02,
                  *,
@@ -317,8 +322,8 @@ def __init__(self, fig,
             as a three-digit subplot position code (e.g., "121").
         nrows_ncols : (int, int)
             Number of rows and columns in the grid.
-        ngrids : int or None, default: None
-            If not None, only the first *ngrids* axes in the grid are created.
+        n_axes : int or None, default: None
+            If not None, only the first *n_axes* axes in the grid are created.
         direction : {"row", "column"}, default: "row"
             Whether axes are created in row-major ("row by row") or
             column-major order ("column by column").  This also affects the
@@ -372,7 +377,7 @@ def __init__(self, fig,
         # The colorbar axes are created in _init_locators().
 
         super().__init__(
-            fig, rect, nrows_ncols, ngrids,
+            fig, rect, nrows_ncols, n_axes,
             direction=direction, axes_pad=axes_pad,
             share_all=share_all, share_x=True, share_y=True, aspect=aspect,
             label_mode=label_mode, axes_class=axes_class)
@@ -408,7 +413,7 @@ def _init_locators(self):
             _cbaraxes_class_factory(self._defaultAxesClass)(
                 self.axes_all[0].get_figure(root=False), self._divider.get_position(),
                 orientation=self._colorbar_location)
-            for _ in range(self.ngrids)]
+            for _ in range(self.n_axes)]
 
         cb_mode = self._colorbar_mode
         cb_location = self._colorbar_location
@@ -429,7 +434,7 @@ def _init_locators(self):
                 v.append(Size.from_any(self._colorbar_size, sz))
                 v.append(Size.from_any(self._colorbar_pad, sz))
                 locator = self._divider.new_locator(nx=0, nx1=-1, ny=0)
-            for i in range(self.ngrids):
+            for i in range(self.n_axes):
                 self.cbar_axes[i].set_visible(False)
             self.cbar_axes[0].set_axes_locator(locator)
             self.cbar_axes[0].set_visible(True)
@@ -490,7 +495,7 @@ def _init_locators(self):
                 v_cb_pos.append(len(v))
                 v.append(Size.from_any(self._colorbar_size, sz))
 
-        for i in range(self.ngrids):
+        for i in range(self.n_axes):
             col, row = self._get_col_row(i)
             locator = self._divider.new_locator(nx=h_ax_pos[col],
                                                 ny=v_ax_pos[self._nrows-1-row])
@@ -530,12 +535,12 @@ def _init_locators(self):
                 v.append(Size.from_any(self._colorbar_size, sz))
                 locator = self._divider.new_locator(nx=0, nx1=-1, ny=-2)
             if cb_location in ("right", "top"):
-                for i in range(self.ngrids):
+                for i in range(self.n_axes):
                     self.cbar_axes[i].set_visible(False)
                 self.cbar_axes[0].set_axes_locator(locator)
                 self.cbar_axes[0].set_visible(True)
         elif cb_mode == "each":
-            for i in range(self.ngrids):
+            for i in range(self.n_axes):
                 self.cbar_axes[i].set_visible(True)
         elif cb_mode == "edge":
             if cb_location in ("right", "left"):
@@ -544,10 +549,10 @@ def _init_locators(self):
                 count = self._ncols
             for i in range(count):
                 self.cbar_axes[i].set_visible(True)
-            for j in range(i + 1, self.ngrids):
+            for j in range(i + 1, self.n_axes):
                 self.cbar_axes[j].set_visible(False)
         else:
-            for i in range(self.ngrids):
+            for i in range(self.n_axes):
                 self.cbar_axes[i].set_visible(False)
                 self.cbar_axes[i].set_position([1., 1., 0.001, 0.001],
                                                which="active")

lib/mpl_toolkits/axes_grid1/tests/test_axes_grid1.py

@@ -104,7 +104,6 @@ def test_axesgrid_colorbar_log_smoketest():
     fig = plt.figure()
     grid = AxesGrid(fig, 111,  # modified to be only subplot
                     nrows_ncols=(1, 1),
-                    ngrids=1,
                     label_mode="L",
                     cbar_location="top",
                     cbar_mode="single",
@@ -638,15 +637,15 @@ def test_grid_axes_position(direction):
     assert loc[3].args[1] == loc[2].args[1]
 
 
-@pytest.mark.parametrize('rect, ngrids, error, message', (
+@pytest.mark.parametrize('rect, n_axes, error, message', (
     ((1, 1), None, TypeError, "Incorrect rect format"),
-    (111, -1, ValueError, "ngrids must be positive"),
-    (111, 7, ValueError, "ngrids must be positive"),
+    (111, -1, ValueError, "n_axes must be positive"),
+    (111, 7, ValueError, "n_axes must be positive"),
 ))
-def test_grid_errors(rect, ngrids, error, message):
+def test_grid_errors(rect, n_axes, error, message):
     fig = plt.figure()
     with pytest.raises(error, match=message):
-        Grid(fig, rect, (2, 3), ngrids=ngrids)
+        Grid(fig, rect, (2, 3), n_axes=n_axes)
 
 
 @pytest.mark.parametrize('anchor, error, message', (
@@ -780,3 +779,9 @@ def test_anchored_locator_base_call():
 def test_grid_with_axes_class_not_overriding_axis():
     Grid(plt.figure(), 111, (2, 2), axes_class=mpl.axes.Axes)
     RGBAxes(plt.figure(), 111, axes_class=mpl.axes.Axes)
+
+
+def test_grid_n_axes():
+    fig = plt.figure()
+    grid = Grid(fig, 111, (3, 3), n_axes=5)
+    assert len(fig.axes) == grid.n_axes == 5