Don't run global frameshift plot when there are no reads (#226)

When there are no reads (i.e. global_MODIFIED_FRAMESHIFT +
global_MODIFIED_NON_FRAMESHIFT + global_NON_MODIFIED_NON_FRAMESHIFT == 0) there
was a bug when trying to compute the pie chart, because all of the values in the
pie chart are 0. This fix, will make sure that there is at least one read in
order for the plot to bee constructed properly.

CRISPResso2/CRISPRessoCORE.py

@@ -4485,26 +4485,27 @@ def count_alternate_alleles(sub_base_vectors, ref_name, ref_sequence, ref_total_
                     global_count_unmodified += counts_unmodified[ref_name]
 
             if not args.suppress_plots:
-                plot_root = _jp('5a.Global_frameshift_in-frame_mutations_pie_chart')
-                plot_5a_input = {
-                    'global_modified_frameshift': global_MODIFIED_FRAMESHIFT,
-                    'global_modified_non_frameshift': global_MODIFIED_NON_FRAMESHIFT,
-                    'global_non_modified_non_frameshift': global_NON_MODIFIED_NON_FRAMESHIFT,
-                    'plot_root': plot_root,
-                    'save_also_png': save_png,
-                }
-                if n_processes > 1:
-                    plot_results.append(plot_pool.submit(
-                        CRISPRessoPlot.plot_global_frameshift_analysis,
-                        **plot_5a_input,
-                    ))
-                else:
-                    CRISPRessoPlot.plot_global_frameshift_analysis(
-                        **plot_5a_input,
-                    )
-                crispresso2_info['results']['general_plots']['plot_5a_root'] = os.path.basename(plot_root)
-                crispresso2_info['results']['general_plots']['plot_5a_caption'] = "Figure 5a: Frameshift analysis of coding sequence reads affected by modifications for all reads. Unmodified reference reads are excluded from this plot, and all HDR reads are included in this plot."
-                crispresso2_info['results']['general_plots']['plot_5a_data'] = []
+                if (global_MODIFIED_FRAMESHIFT + global_MODIFIED_NON_FRAMESHIFT + global_NON_MODIFIED_NON_FRAMESHIFT) > 0:
+                    plot_root = _jp('5a.Global_frameshift_in-frame_mutations_pie_chart')
+                    plot_5a_input = {
+                        'global_modified_frameshift': global_MODIFIED_FRAMESHIFT,
+                        'global_modified_non_frameshift': global_MODIFIED_NON_FRAMESHIFT,
+                        'global_non_modified_non_frameshift': global_NON_MODIFIED_NON_FRAMESHIFT,
+                        'plot_root': plot_root,
+                        'save_also_png': save_png,
+                    }
+                    if n_processes > 1:
+                        plot_results.append(plot_pool.submit(
+                            CRISPRessoPlot.plot_global_frameshift_analysis,
+                            **plot_5a_input,
+                        ))
+                    else:
+                        CRISPRessoPlot.plot_global_frameshift_analysis(
+                            **plot_5a_input,
+                        )
+                    crispresso2_info['results']['general_plots']['plot_5a_root'] = os.path.basename(plot_root)
+                    crispresso2_info['results']['general_plots']['plot_5a_caption'] = "Figure 5a: Frameshift analysis of coding sequence reads affected by modifications for all reads. Unmodified reference reads are excluded from this plot, and all HDR reads are included in this plot."
+                    crispresso2_info['results']['general_plots']['plot_5a_data'] = []
 
                  #profiles-----------------------------------------------------------------------------------
                 plot_root = _jp('6a.Global_frameshift_in-frame_mutation_profiles')