fix histogram issue of default binning method

demo.py

@@ -40,7 +40,8 @@
         writer.add_text('Text', 'text logged at step:'+str(n_iter), n_iter)
         writer.add_text('markdown Text', '''a|b\n-|-\nc|d''', n_iter)
         for name, param in resnet18.named_parameters():
-            writer.add_histogram(name, param, n_iter)
+            if 'bn' not in name:            
+                writer.add_histogram(name, param, n_iter)
         writer.add_pr_curve('xoxo', np.random.randint(2, size=100), np.random.rand(100), n_iter) #needs tensorboard 0.4RC or later
         writer.add_pr_curve_raw('prcurve with raw data', true_positive_counts,
             false_positive_counts,

tensorboardX/summary.py

@@ -119,7 +119,19 @@ def make_histogram(values, bins):
     values = values.reshape(-1)
     counts, limits = np.histogram(values, bins=bins)
     limits = limits[1:]
-
+    # void Histogram::EncodeToProto in histogram.cc
+    for i, c in enumerate(counts):
+        if c > 0:
+            break
+    start = i - 1
+
+    for i, c in enumerate(reversed(counts)):
+        if c > 0:
+            break
+    end = -(i)
+
+    counts = counts[start:end]
+    limits = limits[start:end]
     sum_sq = values.dot(values)
     return HistogramProto(min=values.min(),
                           max=values.max(),