chore: import upstream snapshot with attribution

PFPO/visualize/reward_histogram.py

@@ -0,0 +1,34 @@
+import matplotlib.pyplot as plt
+import numpy as np
+from collections import defaultdict
+import json
+import torch
+import argparse
+
+
+def plot_histogram(data, bins=10, x_label="Value", y_label="Frequency", title="Histogram", output_file="histogram.png"):
+    plt.hist(data, bins=bins, edgecolor='black', alpha=0.7)
+    plt.xlabel(x_label)
+    plt.ylabel(y_label)
+    plt.title(title)
+    plt.grid(True)
+    # plt.show()
+    plt.savefig(output_file)
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--input_file", type=str, required=True)
+    parser.add_argument("--output_file", type=str, default="histogram.png")
+    args = parser.parse_args()
+
+    rewards = json.load(open(args.input_file))
+    if isinstance(rewards[0]["reward"], list):
+        rewards = [item["reward"][0] for item in rewards]
+    else:
+        rewards = [item["reward"] for item in rewards]
+    plot_histogram(rewards, bins=20, x_label="Reward", y_label="Frequency", title="Reward Histogram")
+
+
+if __name__ == "__main__":
+    main()