Add description about density and tests

thoo · thoo · commit 653be4ed96b5 · 2018-10-21T02:47:21.000-04:00
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -6878,6 +6878,9 @@ def hist2d(self, x, y, bins=10, range=None, density=None, weights=None,
           keyword argument. Likewise, power-law normalization (similar
           in effect to gamma correction) can be accomplished with
           `.colors.PowerNorm`.
+        - Numpy 1.15 introduced a 'density' kwarg to hist2d. Even though
+          Numpy 1.15 isn't required, 'density' kwarg is introduced
+          and passed as 'normed' to ``hist2d``.
         """
 
         if density is not None and normed is not None:
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
@@ -1672,6 +1672,30 @@ def test_hist2d():
     ax.hist2d("x", "y", bins=10, data=data, rasterized=True)
 
 
+@pytest.mark.parametrize('density', [False, True])
+def test_hist2d_density(density):
+    # Test density kwarg
+    x = np.random.randn(100)*2+5
+    y = np.random.randn(100)-2
+    fig = plt.figure()
+    ax = fig.add_subplot(111)
+    ax.hist2d(x, y, bins=10, rasterized=True, density=density)
+
+
+@pytest.mark.parametrize('normed', [False, True])
+@pytest.mark.parametrize('density', [False, True])
+def test_hist2d_normed_density(density, normed):
+    # Normed and density should not be used simultaneously
+    x = np.random.randn(100)*2+5
+    y = np.random.randn(100)-2
+    fig = plt.figure()
+    ax = fig.add_subplot(111)
+    # test that kwargs normed and density cannot be set both.
+    with pytest.raises(ValueError, match="kwargs 'density' and 'normed'"):
+        ax.hist2d(x, y, bins=10, rasterized=True,
+                  density=density, normed=normed)
+
+
 @image_comparison(baseline_images=['hist2d_transpose'],
         remove_text=True, style='mpl20')
 def test_hist2d_transpose():
