Fixes to make doctests pass.

skimage/exposure/exposure.py

@@ -36,11 +36,11 @@ def histogram(image, nbins=256):
 
     Examples
     --------
-    >>> camera = skimage.data.camera()
-    >>> hi = exposure.histogram(camera)
-    >>> # Plot histogram
+    >>> from skimage import data
+    >>> hist = histogram(data.camera())
     >>> import matplotlib.pyplot as plt
-    >>> plt.plot(hi[1], hi[0])
+    >>> plt.plot(hist[1], hist[0])  # doctest: +ELLIPSIS
+    [...]
     """
 
     # For integer types, histogramming with bincount is more efficient.

skimage/filter/ctmf.py

@@ -46,7 +46,7 @@ def median_filter(image, radius=2, mask=None, percent=50):
     --------
     >>> a = np.ones((5, 5))
     >>> a[2, 2] = 10 # introduce outlier
-    >>> b = filter.median_filter(a)
+    >>> b = median_filter(a)
     >>> b[2, 2] # the median filter is good at removing outliers
     1.0
     '''

skimage/measure/find_contours.py

@@ -103,7 +103,7 @@ def find_contours(array, level,
     array([[ 1.,  0.,  0.],
            [ 0.,  0.,  0.],
            [ 0.,  0.,  0.]])
-    >>> measure.find_contours(a, 0.5)
+    >>> find_contours(a, 0.5)
     [array([[ 0. ,  0.5],
            [ 0.5,  0. ]])]
     """