Use matplotlib for lab6 visuals and expand report

lab6/aco.py

@@ -1,10 +1,10 @@
 import math
 import random
-import struct
-import zlib
 from dataclasses import dataclass
 from typing import List, Sequence, Tuple
 
+import matplotlib.pyplot as plt
+
 City = Tuple[float, float]
 Tour = List[int]
 
@@ -23,116 +23,38 @@ def build_distance_matrix(cities: Sequence[City]) -> list[list[float]]:
     return matrix
 
 
-def _write_png(filename: str, pixels: list[list[tuple[int, int, int]]]) -> None:
-    height = len(pixels)
-    width = len(pixels[0]) if height else 0
-
-    def chunk(chunk_type: bytes, data: bytes) -> bytes:
-        return (
-            struct.pack(">I", len(data))
-            + chunk_type
-            + data
-            + struct.pack(">I", zlib.crc32(chunk_type + data) & 0xFFFFFFFF)
-        )
-
-    raw = b"".join(b"\x00" + bytes([c for px in row for c in px]) for row in pixels)
-    png = b"\x89PNG\r\n\x1a\n"
-    ihdr = struct.pack(">IIBBBBB", width, height, 8, 2, 0, 0, 0)
-    png += chunk(b"IHDR", ihdr)
-    png += chunk(b"IDAT", zlib.compress(raw, 9))
-    png += chunk(b"IEND", b"")
-
-    with open(filename, "wb") as f:
-        f.write(png)
-
-
-def _scale_points(points: Sequence[tuple[float, float]], size: int = 800, margin: int = 20):
-    xs = [p[0] for p in points]
-    ys = [p[1] for p in points]
-    min_x, max_x = min(xs), max(xs)
-    min_y, max_y = min(ys), max(ys)
-    scale_x = (size - 2 * margin) / (max_x - min_x + 1e-9)
-    scale_y = (size - 2 * margin) / (max_y - min_y + 1e-9)
-    return [
-        (
-            int((x - min_x) * scale_x + margin),
-            int((y - min_y) * scale_y + margin),
-        )
-        for x, y in points
-    ]
-
-
-def _draw_line(pixels: list[list[tuple[int, int, int]]], p1: tuple[int, int], p2: tuple[int, int], color: tuple[int, int, int]):
-    x1, y1 = p1
-    x2, y2 = p2
-    dx = abs(x2 - x1)
-    dy = -abs(y2 - y1)
-    sx = 1 if x1 < x2 else -1
-    sy = 1 if y1 < y2 else -1
-    err = dx + dy
-    while True:
-        if 0 <= x1 < len(pixels[0]) and 0 <= y1 < len(pixels):
-            pixels[y1][x1] = color
-        if x1 == x2 and y1 == y2:
-            break
-        e2 = 2 * err
-        if e2 >= dy:
-            err += dy
-            x1 += sx
-        if e2 <= dx:
-            err += dx
-            y1 += sy
-
-
-def _draw_circle(pixels: list[list[tuple[int, int, int]]], center: tuple[int, int], radius: int, color: tuple[int, int, int]):
-    cx, cy = center
-    for y in range(cy - radius, cy + radius + 1):
-        for x in range(cx - radius, cx + radius + 1):
-            if 0 <= x < len(pixels[0]) and 0 <= y < len(pixels):
-                if (x - cx) ** 2 + (y - cy) ** 2 <= radius ** 2:
-                    pixels[y][x] = color
-
-
 def plot_tour(cities: Sequence[City], tour: Sequence[int], save_path: str) -> None:
     ordered = [cities[i] for i in tour] + [cities[tour[0]]]
-    points = _scale_points(ordered)
-    width = height = 820
-    pixels = [[(255, 255, 255) for _ in range(width)] for _ in range(height)]
+    xs, ys = zip(*ordered)
 
-    for i in range(len(points) - 1):
-        _draw_line(pixels, points[i], points[i + 1], (0, 120, 200))
+    fig, ax = plt.subplots(figsize=(7, 7))
+    ax.plot(xs, ys, "-o", color="#1f77b4", markersize=4, linewidth=1.5)
+    city_xs, city_ys = zip(*cities)
+    ax.scatter(city_xs, city_ys, s=18, color="#d62728", zorder=5)
 
-    # draw cities
-    city_points = _scale_points(cities)
-    for p in city_points:
-        _draw_circle(pixels, p, 4, (200, 50, 50))
-
-    _write_png(save_path, pixels)
+    ax.set_xlabel("X")
+    ax.set_ylabel("Y")
+    ax.set_title("Маршрут тура")
+    ax.set_aspect("equal", adjustable="box")
+    ax.grid(True, linestyle="--", alpha=0.3)
+    fig.tight_layout()
+    fig.savefig(save_path, dpi=220)
+    plt.close(fig)
 
 
 def plot_history(best_lengths: Sequence[float], save_path: str) -> None:
     if not best_lengths:
         return
 
-    width, height, margin = 820, 400, 20
-    pixels = [[(255, 255, 255) for _ in range(width)] for _ in range(height)]
-
-    n = len(best_lengths)
-    min_len, max_len = min(best_lengths), max(best_lengths)
-    span = max_len - min_len if max_len != min_len else 1
-
-    def to_point(idx: int, value: float) -> tuple[int, int]:
-        x = margin + int((width - 2 * margin) * idx / max(1, n - 1))
-        y = height - margin - int((height - 2 * margin) * (value - min_len) / span)
-        return x, y
-
-    prev = to_point(0, best_lengths[0])
-    for i, v in enumerate(best_lengths[1:], start=1):
-        cur = to_point(i, v)
-        _draw_line(pixels, prev, cur, (30, 30, 30))
-        prev = cur
-
-    _write_png(save_path, pixels)
+    fig, ax = plt.subplots(figsize=(8, 3.8))
+    ax.plot(best_lengths, color="#111111", linewidth=1.4)
+    ax.set_xlabel("Итерация")
+    ax.set_ylabel("Длина лучшего тура")
+    ax.set_title("Сходимость ACO")
+    ax.grid(True, linestyle="--", alpha=0.4)
+    fig.tight_layout()
+    fig.savefig(save_path, dpi=220)
+    plt.close(fig)
 
 
 @dataclass