ml changes

spras/analysis/ml.py

@@ -41,10 +41,13 @@ def summarize_networks(file_paths: Iterable[Union[str, PathLike]]) -> pd.DataFra
             with open(file, 'r') as f:
                 lines = f.readlines()
 
+            if len(lines) > 0:
+                lines.pop(0) # process header line 
+
             edges = []
             for line in lines:
                 parts = line.split('\t')
-                if len(parts) == 4:
+                if len(parts) == 4: # empty lines not allowed but empty files are allowed
                     node1 = parts[0]
                     node2 = parts[1]
                     direction = str(parts[3]).strip()
@@ -56,8 +59,9 @@ def summarize_networks(file_paths: Iterable[Union[str, PathLike]]) -> pd.DataFra
                         edges.append(DIR_CONST.join([node1, node2]))
                     elif direction != 'Direction' and direction != 'U' and direction != 'D':
                         raise ValueError(f"direction is {direction}, rather than U or D")
-                elif len(parts) > 4 or (len(parts) < 4 and len(parts) > 0): # empty line in file is okay
-                    raise ValueError(f"A line in pathway file {file} contains {len(parts)} values. There should be 4 values per line")
+                elif len(parts) != 0:
+                    raise ValueError(f"In file {file}, expected line {line} to have 4 values, but found {len(parts)} values.")
+
             # getting the algorithm name
             p = PurePath(file)
             edge_tuples.append((p.parts[-2], edges))