csv_2_plot: improve plot configuration and add average voltage/interval calculations

Signed-off-by: YoungSoo Shin <shinys000114@gmail.com>

example/logger/csv_2_plot.py

@@ -3,6 +3,7 @@ import matplotlib.dates as mdates
 import matplotlib.pyplot as plt
 import pandas as pd
 from dateutil.tz import gettz
+from matplotlib.ticker import MultipleLocator
 
 
 def plot_power_data(csv_path, output_path, plot_types, sources):
@@ -19,16 +20,11 @@ def plot_power_data(csv_path, output_path, plot_types, sources):
     """
     try:
         # Read the CSV file into a pandas DataFrame
-        # The 'timestamp' column is parsed as dates. Pandas automatically recognizes
-        # the ISO format (with 'Z') as UTC.
         df = pd.read_csv(csv_path, parse_dates=['timestamp'])
         print(f"Successfully loaded {len(df)} records from '{csv_path}'")
 
         # --- Timezone Conversion ---
-        # Get the system's local timezone
         local_tz = gettz()
-        # The timestamp from CSV is already UTC-aware.
-        # Convert it to the system's local timezone for plotting.
         df['timestamp'] = df['timestamp'].dt.tz_convert(local_tz)
         print(f"Timestamp converted to local timezone: {local_tz}")
 
@@ -39,24 +35,32 @@ def plot_power_data(csv_path, output_path, plot_types, sources):
         print(f"An error occurred while reading the CSV file: {e}")
         return
 
+    # --- Calculate Average Interval ---
+    avg_interval_ms = 0
+    if len(df) > 1:
+        avg_interval = df['timestamp'].diff().mean()
+        avg_interval_ms = avg_interval.total_seconds() * 1000
+
+    # --- Calculate Average Voltages ---
+    avg_voltages = {}
+    for source in sources:
+        voltage_col = f'{source}_voltage'
+        if voltage_col in df.columns:
+            avg_voltages[source] = df[voltage_col].mean()
+
     # --- Plotting Configuration ---
-    # Y-axis scale settings from chart.js
     scale_config = {
         'power': {'steps': [5, 20, 50, 160]},
         'voltage': {'steps': [5, 10, 15, 25]},
         'current': {'steps': [1, 2.5, 5, 10]}
     }
-
     plot_configs = {
-        'power': {'title': 'Power Consumption', 'ylabel': 'Power (W)',
+        'power': {'title': 'Power Consumption', 'ylabel': 'Power (W)', 'cols': [f'{s}_power' for s in sources]},
-                  'cols': [f'{s}_power' for s in sources]},
+        'voltage': {'title': 'Voltage', 'ylabel': 'Voltage (V)', 'cols': [f'{s}_voltage' for s in sources]},
-        'voltage': {'title': 'Voltage', 'ylabel': 'Voltage (V)',
+        'current': {'title': 'Current', 'ylabel': 'Current (A)', 'cols': [f'{s}_current' for s in sources]}
-                    'cols': [f'{s}_voltage' for s in sources]},
-        'current': {'title': 'Current', 'ylabel': 'Current (A)',
-                    'cols': [f'{s}_current' for s in sources]}
     }
+
     channel_labels = [s.upper() for s in sources]
-    # Define a color map for all possible sources
     color_map = {'vin': 'red', 'main': 'green', 'usb': 'blue'}
     channel_colors = [color_map[s] for s in sources]
 
@@ -65,20 +69,17 @@ def plot_power_data(csv_path, output_path, plot_types, sources):
         print("No plot types selected. Exiting.")
         return
 
-    # Create a figure and a set of subplots based on the number of selected plot types.
+    fig, axes = plt.subplots(num_plots, 1, figsize=(15, 9 * num_plots), sharex=True, squeeze=False)
-    fig, axes = plt.subplots(num_plots, 1, figsize=(15, 6 * num_plots), sharex=True, squeeze=False)
+    axes = axes.flatten()
-    axes = axes.flatten()  # Flatten the 2D array to 1D for easier iteration
 
     # --- Loop through selected plot types and generate plots ---
     for i, plot_type in enumerate(plot_types):
         ax = axes[i]
         config = plot_configs[plot_type]
-
         max_data_value = 0
         for j, col_name in enumerate(config['cols']):
             if col_name in df.columns:
-                ax.plot(df['timestamp'], df[col_name], label=channel_labels[j], color=channel_colors[j])
+                ax.plot(df['timestamp'], df[col_name], label=channel_labels[j], color=channel_colors[j], zorder=2)
-                # Find the maximum value in the current column to set the y-axis limit
                 max_col_value = df[col_name].max()
                 if max_col_value > max_data_value:
                     max_data_value = max_col_value
@@ -86,34 +87,82 @@ def plot_power_data(csv_path, output_path, plot_types, sources):
                 print(f"Warning: Column '{col_name}' not found in CSV. Skipping.")
 
         # --- Dynamic Y-axis Scaling ---
-        ax.set_ylim(bottom=0) # Set y-axis minimum to 0
+        ax.set_ylim(bottom=0)
         if plot_type in scale_config:
             steps = scale_config[plot_type]['steps']
-            # Find the smallest step that is >= max_data_value
             new_max = next((step for step in steps if step >= max_data_value), steps[-1])
             ax.set_ylim(top=new_max)
 
         ax.set_title(config['title'])
         ax.set_ylabel(config['ylabel'])
         ax.legend()
-        ax.grid(True, which='both', linestyle='--', linewidth=0.5)
+
+        # --- Grid and Tick Configuration ---
+        y_min, y_max = ax.get_ylim()
+
+        # Keep the dynamic major_interval logic for tick LABELS
+        if plot_type == 'current' and y_max <= 2.5:
+            major_interval = 0.5
+        elif y_max <= 10:
+            major_interval = 2
+        elif y_max <= 25:
+            major_interval = 5
+        else:
+            major_interval = y_max / 5.0
+
+        ax.yaxis.set_major_locator(MultipleLocator(major_interval))
+        ax.yaxis.set_minor_locator(MultipleLocator(1))
+
+        # Disable the default major grid, but keep the minor one
+        ax.yaxis.grid(False, which='major')
+        ax.yaxis.grid(True, which='minor', linestyle='--', linewidth=0.6, zorder=0)
+
+        # Draw custom lines for 5 and 10 multiples, which are now the only major grid lines
+        for y_val in range(int(y_min), int(y_max) + 1):
+            if y_val == 0: continue
+            if y_val % 10 == 0:
+                ax.axhline(y=y_val, color='green', linestyle='-', linewidth=1.0, zorder=1)
+            elif y_val % 5 == 0:
+                ax.axhline(y=y_val, color='red', linestyle='-', linewidth=1.0, zorder=1)
+
+        # Keep the x-axis grid
+        ax.xaxis.grid(True, which='major', linestyle='--', linewidth=0.8)
 
     # --- Formatting the x-axis (Time) ---
     local_tz = gettz()
     last_ax = axes[-1]
-    # Pass the timezone to the formatter
+
+    if not df.empty:
+        last_ax.set_xlim(df['timestamp'].iloc[0], df['timestamp'].iloc[-1])
+
     last_ax.xaxis.set_major_formatter(mdates.DateFormatter('%H:%M:%S', tz=local_tz))
-    last_ax.xaxis.set_major_locator(plt.MaxNLocator(15))  # Limit the number of ticks
+    last_ax.xaxis.set_major_locator(plt.MaxNLocator(15))
-    plt.xlabel(f'Time ({local_tz.tzname(df["timestamp"].iloc[-1])})') # Display timezone name
+    plt.xlabel(f'Time ({local_tz.tzname(df["timestamp"].iloc[-1])})')
     plt.xticks(rotation=45)
 
-    # Add a main title to the figure
+    # --- Add a main title and subtitle ---
     start_time = df['timestamp'].iloc[0].strftime('%Y-%m-%d %H:%M:%S')
     end_time = df['timestamp'].iloc[-1].strftime('%H:%M:%S')
-    fig.suptitle(f'PowerMate Log ({start_time} to {end_time})', fontsize=16, y=0.95)
+    main_title = f'PowerMate Log ({start_time} to {end_time})'
 
-    # Adjust layout to prevent titles/labels from overlapping
+    subtitle_parts = []
-    plt.tight_layout(rect=[0, 0, 1, 0.94])
+    if avg_interval_ms > 0:
+        subtitle_parts.append(f'Avg. Interval: {avg_interval_ms:.2f} ms')
+
+    voltage_strings = [f'{source.upper()} Avg: {avg_v:.2f} V' for source, avg_v in avg_voltages.items()]
+    if voltage_strings:
+        subtitle_parts.extend(voltage_strings)
+
+    subtitle = ' | '.join(subtitle_parts)
+
+    full_title = main_title
+    if subtitle:
+        full_title += f'\n{subtitle}'
+
+    fig.suptitle(full_title, fontsize=14)
+
+    # Adjust layout to make space for the subtitle
+    plt.tight_layout(rect=[0, 0, 1, 0.93])
 
     # --- Save the plot to a file ---
     try: