Merge pull request #1971 from mccode-dev/farhi-mcplot-log10-ymin-0

Update plotfuncs.py: fix log scale when min(data) ~ 0

Author: willend

tools/Python/mcplot/pyqtgraph/plotfuncs.py

@@ -197,6 +197,8 @@ def plot_Data2D(data, plt, log=False, legend=True, icolormap=0, verbose=False, f
         idx = dataset[dataset>0]
         if len(idx) > 0:
             ymin = np.min(idx)/10
+            if ymin <= 0:
+                ymin=100*sys.float_info.min # Small, finite value.
             dataset[dataset<=0] = ymin
             dataset = np.reshape(dataset, datashape)
             dataset = np.log10(dataset)