Replace np.empty + ndarray.fill by np.full.

anntzer · anntzer · commit 4c1a88f3963e · 2019-01-27T20:19:33.000+01:00
except for demo_agg_filter.py, which can be further simplified to use
np.pad.
diff --git a/examples/images_contours_and_fields/image_transparency_blend.py b/examples/images_contours_and_fields/image_transparency_blend.py
@@ -48,8 +48,7 @@ def normal_pdf(x, mean, var):
 weights = weights_high + weights_low
 
 # We'll also create a grey background into which the pixels will fade
-greys = np.empty(weights.shape + (3,), dtype=np.uint8)
-greys.fill(70)
+greys = np.full((*weights.shape, 3), 70, dtype=np.uint8)
 
 # First we'll plot these blobs using only ``imshow``.
 vmax = np.abs(weights).max()
diff --git a/examples/misc/demo_agg_filter.py b/examples/misc/demo_agg_filter.py
@@ -145,17 +145,13 @@ def __init__(self, pixels, color=None):
             self.color = color
 
     def __call__(self, im, dpi):
-        pad = self.pixels
         ny, nx, depth = im.shape
-        new_im = np.empty([pad*2 + ny, pad*2 + nx, depth], dtype="d")
-        alpha = new_im[:, :, 3]
-        alpha.fill(0)
-        alpha[pad:-pad, pad:-pad] = im[:, :, -1]
+        alpha = np.pad(im[..., -1], self.pixels, "constant")
         alpha2 = np.clip(smooth2d(alpha, self.pixels/72.*dpi) * 5, 0, 1)
+        new_im = np.empty((*alpha2.shape, 4))
         new_im[:, :, -1] = alpha2
         new_im[:, :, :-1] = self.color
-        offsetx, offsety = -pad, -pad
-
+        offsetx, offsety = -self.pixels, -self.pixels
         return new_im, offsetx, offsety
 
 
diff --git a/lib/matplotlib/tests/test_mlab.py b/lib/matplotlib/tests/test_mlab.py
@@ -127,10 +127,9 @@ def test_stride_windows_n32_noverlap0_unflatten(self, axis):
 
     def test_stride_ensure_integer_type(self):
         N = 100
-        x = np.empty(N + 20, dtype='>f4')
-        x.fill(np.NaN)
+        x = np.full(N + 20, np.nan)
         y = x[10:-10]
-        y.fill(0.3)
+        y[:] = 0.3
         # previous to #3845 lead to corrupt access
         y_strided = mlab.stride_windows(y, n=33, noverlap=0.6)
         assert_array_equal(y_strided, 0.3)
diff --git a/lib/mpl_toolkits/axisartist/floating_axes.py b/lib/mpl_toolkits/axisartist/floating_axes.py
@@ -112,8 +112,7 @@ def transform_xy(x, y):
 
         # find angles
         if self.nth_coord == 0:
-            xx0 = np.empty_like(yy0)
-            xx0.fill(self.value)
+            xx0 = np.full_like(yy0, self.value)
 
             xx1, yy1 = transform_xy(xx0, yy0)
 
@@ -131,8 +130,7 @@ def transform_xy(x, y):
             labels = [l for l, m in zip(labels, mask) if m]
 
         elif self.nth_coord == 1:
-            yy0 = np.empty_like(xx0)
-            yy0.fill(self.value)
+            yy0 = np.full_like(xx0, self.value)
 
             xx1, yy1 = transform_xy(xx0, yy0)
 
@@ -372,15 +370,13 @@ def get_boundary(self):
         """
         x0, x1, y0, y1 = self._extremes
         tr = self._aux_trans
-        xx = np.linspace(x0, x1, 100)
-        yy0, yy1 = np.empty_like(xx), np.empty_like(xx)
-        yy0.fill(y0)
-        yy1.fill(y1)
 
+        xx = np.linspace(x0, x1, 100)
+        yy0 = np.full_like(xx, y0)
+        yy1 = np.full_like(xx, y1)
         yy = np.linspace(y0, y1, 100)
-        xx0, xx1 = np.empty_like(yy), np.empty_like(yy)
-        xx0.fill(x0)
-        xx1.fill(x1)
+        xx0 = np.full_like(yy, x0)
+        xx1 = np.full_like(yy, x1)
 
         xxx = np.concatenate([xx[:-1], xx1[:-1], xx[-1:0:-1], xx0])
         yyy = np.concatenate([yy0[:-1], yy[:-1], yy1[:-1], yy[::-1]])
diff --git a/lib/mpl_toolkits/axisartist/grid_helper_curvelinear.py b/lib/mpl_toolkits/axisartist/grid_helper_curvelinear.py
@@ -231,8 +231,7 @@ def transform_xy(x, y):
 
         # find angles
         if self.nth_coord == 0:
-            xx0 = np.empty_like(yy0)
-            xx0.fill(self.value)
+            xx0 = np.full_like(yy0, self.value)
 
             xx1, yy1 = transform_xy(xx0, yy0)
 
@@ -248,8 +247,7 @@ def transform_xy(x, y):
             labels = [l for l, m in zip(labels, mask) if m]
 
         elif self.nth_coord == 1:
-            yy0 = np.empty_like(xx0)
-            yy0.fill(self.value)
+            yy0 = np.full_like(xx0, self.value)
 
             xx1, yy1 = transform_xy(xx0, yy0)
 
diff --git a/lib/mpl_toolkits/tests/test_mplot3d.py b/lib/mpl_toolkits/tests/test_mplot3d.py
@@ -706,8 +706,7 @@ def test_named_colors(self):
         x, y, z = np.indices((10, 10, 10))
         voxels = (x == y) | (y == z)
         voxels = voxels & ~(x * y * z < 1)
-        colors = np.zeros((10, 10, 10), dtype=np.object_)
-        colors.fill('C0')
+        colors = np.full((10, 10, 10), 'C0', dtype=np.object_)
         colors[(x < 5) & (y < 5)] = '0.25'
         colors[(x + z) < 10] = 'cyan'
         ax.voxels(voxels, facecolors=colors)
