DOC: Fix some warnings in examples.

In `power_norm`, the input to `multivariate_normal` should be symmetric.
In `scales`, the Mercator equation is ±inf for ±90, so change the limits
to avoid that.
In `demo_text_rotation_mode`, remove a deprecated call.

Author: QuLogic

examples/scales/power_norm.py

@@ -14,7 +14,7 @@
 
 data = np.vstack([
     multivariate_normal([10, 10], [[3, 2], [2, 3]], size=100000),
-    multivariate_normal([30, 20], [[2, 3], [1, 3]], size=1000)
+    multivariate_normal([30, 20], [[3, 1], [1, 3]], size=1000)
 ])
 
 gammas = [0.8, 0.5, 0.3]

examples/scales/scales.py

@@ -87,17 +87,17 @@ def inverse(a):
 
 ax = axs[2, 1]
 
-t = np.arange(-170.0, 170.0, 0.1)
+t = np.arange(0, 170.0, 0.1)
 s = t / 2.
 
 ax.plot(t, s, '-', lw=2)
 
 ax.set_yscale('function', functions=(forward, inverse))
 ax.set_title('function: Mercator')
 ax.grid(True)
-ax.set_xlim([-180, 180])
+ax.set_xlim([0, 180])
 ax.yaxis.set_minor_formatter(NullFormatter())
-ax.yaxis.set_major_locator(FixedLocator(np.arange(-90, 90, 30)))
+ax.yaxis.set_major_locator(FixedLocator(np.arange(0, 90, 10)))
 
 plt.show()
 

examples/text_labels_and_annotations/demo_text_rotation_mode.py

@@ -64,7 +64,7 @@ def test_rotation_mode(fig, mode, subplot_location):
         # highlight bbox
         fig.canvas.draw()
         for ax, tx in zip(grid, texts):
-            bb = tx.get_window_extent().inverse_transformed(ax.transData)
+            bb = tx.get_window_extent().transformed(ax.transData.inverted())
             rect = plt.Rectangle((bb.x0, bb.y0), bb.width, bb.height,
                                  facecolor="C1", alpha=0.3, zorder=2)
             ax.add_patch(rect)