Better handling of empty data in scatterplots.

libhts/libhts.py

@@ -396,9 +396,16 @@ def plot_MA(res,
         else:
             (status, colour) = group2colour
             row_indices = data.index.intersection(grouping)
-            data.ix[row_indices].plot.scatter(
-                x=x_column, y=y_column, s=1, logx=True, c=colour,
-                label=f"{status} ({len(row_indices)})", ax=ax)
+            try:
+                data.ix[row_indices].plot.scatter(
+                    x=x_column, y=y_column, s=1, logx=True, c=colour,
+                    label=f"{status} ({len(row_indices)})", ax=ax)
+            except ValueError as e:
+                if str(e) != "scatter requires x column to be numeric":
+                    print(data.ix[row_indices])
+                    raise
+                else:
+                    warnings.warn(f"Nothing to plot for {status}\n")
     ax.axhline(y=1, linewidth=0.5, color="0.5", linestyle="dashed")
     ax.axhline(y=-1, linewidth=0.5, color="0.5", linestyle="dashed")
     # TODO: check data basemean range
@@ -454,9 +461,16 @@ def plot_scatter(data,
             # Apply a coulour to a list of genes
             (status, colour) = group2colour
             row_indices = data.index.intersection(grouping)
-            data.ix[row_indices].plot.scatter(
-                x=x_column, y=y_column, s=1, c=colour,
-                label=f"{status} ({len(row_indices)})", ax=ax)
+            try:
+                data.ix[row_indices].plot.scatter(
+                    x=x_column, y=y_column, s=1, c=colour,
+                    label=f"{status} ({len(row_indices)})", ax=ax)
+            except ValueError as e:
+                if str(e) != "scatter requires x column to be numeric":
+                    print(data.ix[row_indices])
+                    raise
+                else:
+                    warnings.warn(f"Nothing to plot for {status}\n")
     ax.axhline(y=0, linewidth=0.5, color="0.5", linestyle="dashed")
     ax.axvline(x=0, linewidth=0.5, color="0.5", linestyle="dashed")
     # Set axis limits