# File: frequency.py # Copyright (C) 2026 Erick Ahmed # SPDX-License-Identifier: AGPL-3.0-or-later import argparse from pathlib import Path import numpy as np import pandas as pd import plotly.graph_objects as go from stats.utils.extractor import load_data def _format_can_id_vec(s: pd.Series) -> pd.Series: s = s.astype('string').str.strip() s = s.str.replace(r'^0x', '', case=False, regex=True) s = s.str.upper() return s.fillna('UNKNOWN').replace('', 'UNKNOWN') def calculate_frequency(df: pd.DataFrame) -> pd.DataFrame: can_id_col = 'ID' if 'ID' in df.columns else 'Identifier' formatted = _format_can_id_vec(df[can_id_col]) counts = formatted.value_counts() freq_df = pd.DataFrame({ 'Identifier': counts.index, 'Count': counts.to_numpy(), }) total = counts.sum() freq_df['Percentage'] = np.round(freq_df['Count'] / total * 100, 2) if total else 0.0 return freq_df.sort_values('Count', ascending=True).reset_index(drop=True) def plot_frequency(stats_df: pd.DataFrame, title: str) -> go.Figure: n = len(stats_df) fig = go.Figure(go.Bar( y=stats_df['Identifier'], x=stats_df['Count'], orientation='h', marker=dict( color=stats_df['Count'], colorscale='Turbo', cmin=int(stats_df['Count'].min()) if n else 0, cmax=int(stats_df['Count'].max()) if n else 1, line_width=0, ), customdata=stats_df[['Percentage']].to_numpy(), hovertemplate="%{y}
Count: %{x:,}
Share: %{customdata[0]}%", texttemplate='%{x:,}', textposition='outside', cliponaxis=False, )) fig.update_layout( height=max(600, n * 18), autosize=True, template='plotly_white', xaxis=dict( type='log', title=dict(text="Message count [log scale]", font=dict(size=13, color="#1a1a1a")), side="top", dtick=1, showgrid=False, linecolor="#bdbdbd", tickfont=dict(size=12, color="#2a2a2a"), ticks="outside", ticklen=4, tickcolor="#cccccc", ), yaxis=dict( title=dict(text="PGN or CAN ID", font=dict(size=13, color="#1a1a1a")), showgrid=False, linecolor="#bdbdbd", tickfont=dict(size=12, color="#2a2a2a"), ticks="outside", ticklen=4, tickcolor="#cccccc", automargin=True, type='category', ), font=dict(family="Segoe UI, Arial, sans-serif", size=12, color='#2a2a2a'), hoverlabel=dict(bgcolor="white", font_size=13, font_family="Segoe UI", bordercolor='#cccccc'), margin=dict(l=200, r=40, t=120, b=60), bargap=0.35, coloraxis_colorbar=dict( title=dict(text='Message Count', side='top'), orientation='h', thickness=15, len=0.35, x=1.0, xanchor='right', y=1.02, yanchor='bottom', tickformat=',', outlinecolor='#cccccc', outlinewidth=0.5, ), title=dict(text=title, font=dict(size=20, color='#1a1a1a'), x=0.5, xanchor='center', pad=dict(b=20)), ) fig.update_xaxes( showgrid=True, gridwidth=0.5, gridcolor='#e8e8e8', zeroline=False, linecolor='#bdbdbd', mirror=False, tickformat=',', minor=dict(showgrid=True, gridcolor='#f4f4f4', gridwidth=0.5), ) fig.update_yaxes( showgrid=False, zeroline=False, linecolor='#bdbdbd', ticks='outside', ticklen=4, tickcolor='#cccccc', automargin=True, ) return fig if __name__ == "__main__": 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")) parser.add_argument("title", nargs="?", default="Frequency") args = parser.parse_args() df = load_data(args.input) stats = calculate_frequency(df) fig = plot_frequency(stats, title=args.title) config = { 'responsive': True, 'displaylogo': False, 'scrollZoom': True, 'modeBarButtonsToAdd': ['toggleSpikelines'], 'toImageButtonOptions': {'format': 'png', 'scale': 2}, } fig.write_html(str(args.output), include_plotlyjs='cdn', config=config)