fix a condition test and remove some useless assignment

jhelie · jhelie · commit 7f00354a6a7b · 2017-06-07T10:57:54.000+01:00
diff --git a/examples/pylab_examples/arrow_demo.py b/examples/pylab_examples/arrow_demo.py
@@ -119,8 +119,6 @@ def do_fontsize(k):
 
     arrow_h_offset = 0.25  # data coordinates, empirically determined
     max_arrow_length = 1 - 2*arrow_h_offset
-
-    max_arrow_width = max_arrow_width
     max_head_width = 2.5*max_arrow_width
     max_head_length = 2*max_arrow_width
     arrow_params = {'length_includes_head': True, 'shape': shape,
@@ -164,11 +162,11 @@ def draw_arrow(pair, alpha=alpha, ec=ec, labelcolor=labelcolor):
                                                       max_head_length)
         else:
             length = max_arrow_length
+        
         # set the transparency of the arrow
-        if display == 'alph':
+        if display == 'alpha':
             alpha = min(data[pair]/sf, alpha)
-        else:
-            alpha = alpha
+
         # set the width of the arrow
         if display == 'width':
             scale = data[pair]/sf
diff --git a/lib/matplotlib/mlab.py b/lib/matplotlib/mlab.py
@@ -3881,7 +3881,6 @@ def cross_from_below(x, threshold):
 
     """
     x = np.asarray(x)
-    threshold = threshold
     ind = np.nonzero((x[:-1] < threshold) & (x[1:] >= threshold))[0]
     if len(ind):
         return ind+1
