plot_experiments.py

import os
import pandas as pd
import numpy as np
import matplotlib.pyplot as plt

prefix = "fast_results"
types = ["random", "reversed", "almost_sorted"]
thresholds = [5]
repetitions = 7

def read_csv(path):
    return pd.read_csv(path)

def summarize(df):
    runs = [c for c in df.columns if c.startswith("run")]
    df["median"] = df[runs].median(axis=1)
    df["mean"] = df[runs].mean(axis=1)
    df["q1"] = df[runs].quantile(0.25, axis=1)
    df["q3"] = df[runs].quantile(0.75, axis=1)
    return df

for t in types:
    std_path = f"{prefix}_{t}_std.csv"
    if not os.path.exists(std_path):
        print("Missing", std_path)
        continue
    df_std = summarize(read_csv(std_path))

    plt.figure(figsize=(10,6))
    plt.plot(df_std["size"], df_std["median"], label="merge_std (median)", linewidth=2)
    plt.xlabel("size")
    plt.ylabel("time (ms)")
    plt.title(f"Merge sort standard — {t}")
    plt.grid(True)
    plt.legend()
    plt.savefig(f"plot_{t}_std.png", dpi=200)
    plt.close()

    plt.figure(figsize=(12,8))
    plt.plot(df_std["size"], df_std["median"], label="merge_std (median)", linewidth=2, linestyle='--')
    for thr in thresholds:
        path = f"{prefix}_{t}_hybrid_thr{thr}.csv"
        if not os.path.exists(path): 
            print("Missing", path)
            continue
        df_h = summarize(read_csv(path))
        plt.plot(df_h["size"], df_h["median"], label=f"hybrid thr={thr}")
    plt.xlabel("size")
    plt.ylabel("time (ms)")
    plt.title(f"Merge vs Hybrid (median) — {t}")
    plt.legend()
    plt.grid(True)
    plt.savefig(f"plot_{t}_compare_median.png", dpi=200)
    plt.close()

    plt.figure(figsize=(12,8))
    for thr in thresholds:
        path = f"{prefix}_{t}_hybrid_thr{thr}.csv"
        if not os.path.exists(path): continue
        df_h = summarize(read_csv(path))
        ratio = df_h["median"].values / df_std["median"].values
        plt.plot(df_std["size"], ratio, label=f"thr={thr}")
    plt.axhline(1.0, color='k', linestyle='--')
    plt.xlabel("size")
    plt.ylabel("ratio hybrid/std")
    plt.title(f"Ratio median(hybrid)/median(std) — {t}")
    plt.legend()
    plt.grid(True)
    plt.savefig(f"plot_{t}_ratio.png", dpi=200)
    plt.close()

print("Plots saved. Inspect PNG files.")