Remove requirement for positional arguments

- Makes python recognize it as a submodule

stat/frequency.py

@@ -39,10 +39,10 @@ def plot_freq(stats_df: pd.DataFrame, title: str) -> go.Figure:
     return fig
 
 if __name__ == "__main__":
-    parser = argparse.ArgumentParser(description="Analyze CAN bus frequency.")
-    parser.add_argument("-i", "--input", type=Path, required=True)
-    parser.add_argument("-o", "--output", type=Path, default=Path("freq_report.html"))
-    parser.add_argument("-t", "--title", type=str, default="CAN Bus Message Frequency")
+    parser = argparse.ArgumentParser(description="Analyze CAN bus message frequency")
+    parser.add_argument("input", type=Path, help="Path to the input CAN log file")
+    parser.add_argument("output", type=Path, nargs="?", default=Path("freq_report.html"), help="Path to the output HTML report")
+    parser.add_argument("title", nargs="?", default="CAN Bus Message Frequency", help="Title for the HTML report")
     args = parser.parse_args()
 
     df = load_data(args.input)

stat/utils/extractor.py

@@ -0,0 +1,23 @@
+import json
+from pathlib import Path
+import pandas as pd
+
+def extract_id(row: pd.Series) -> str:
+    """Extracts PGN from metadata or falls back to CAN ID."""
+    meta = row.get('j1939_metadata')
+    if pd.isna(meta):
+        return f"ID: {row['ID']}"
+    if isinstance(meta, str):
+        try:
+            meta = json.loads(meta)
+        except json.JSONDecodeError:
+            return f"ID: {row['ID']}"
+    if isinstance(meta, dict) and 'PGN' in meta:
+        return f"PGN: {meta['PGN']}"
+    return f"ID: {row['ID']}"
+
+def load_data(file_path: Path) -> pd.DataFrame:
+    """Loads Parquet file and adds an Identifier column."""
+    df = pd.read_parquet(file_path)
+    df['Identifier'] = df.apply(extract_id, axis=1)
+    return df