message: filter out all nan series
diff: @@ -1112,16 +1112,22 @@ class NVD3TimeSeriesViz(NVD3Viz):
  series_title = series_title + (title_suffix,)
  values = []
  + non_nan_cnt = 0
  for ds in df.index:
  if ds in ys:
  d = {
  'x': ds,
  'y': ys[ds],
  }
  + if not np.isnan(ys[ds]):
  + non_nan_cnt += 1
  else:
  d = {}
  values.append(d)
  + if non_nan_cnt == 0:
  + continue
  +
  d = {
  'key': series_title,
  'values': values,
  