Python大作业——北印导航系统

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项目成品下载

链接1

¶简介

针对新生对校园了解的不足，帮助新生对校园中的各建筑有更加多方面的了解。同时可以对于校园工作人员优化校园工具的搬运选择最优的运输路径，提高运输的效率。通过对dijkstra算法进行编写，实现从一个顶点到其余各顶点的最短路径算法，解决的有向图中最短路径问题。主要特点是以起始点为中心向外层层扩展，直到扩展到终点为止，是一种广度优先的搜索方法。

程序的数据和地图利用json.dumps方法编码为json文件的方式放在云服务器上，在运行代码的时候利用json.load方法访问服务器端数据。

¶代码

import os
import json
import tkinter
import turtle
import urllib
import urllib.request
from collections import defaultdict
from heapq import heappop, heappush
from math import sqrt
from tkinter import *
from tkinter.ttk import Combobox
from urllib.request import urlretrieve


# 从点str1移动到str2
def move(str1, str2):
    x = point[str1][0] - 953 / 2
    y = 759 / 2 - point[str1][1]
    a = point[str2][0] - 953 / 2
    b = 759 / 2 - point[str2][1]
    turtle.up()
    turtle.goto(x, y)
    turtle.down()
    turtle.goto(a, b)
    turtle.up()


# 判断两点的距离
def distence(str1, str2, paramein, pointin):
    if [str1, str2] in paramein or [str2, str1] in paramein:
        return sqrt((pointin[str1][1] - pointin[str2][1]) ** 2 + (pointin[str1][0] - pointin[str2][0]) ** 2)
    elif pointin[str1][0] == pointin[str2][0]:
        return abs(pointin[str1][1] - pointin[str2][1])
    elif pointin[str1][1] == pointin[str2][1]:
        return abs(pointin[str1][0] - pointin[str2][0])
    else:
        return 1E100


# 优化后Dijkstra算法
def dijkstra(edges, t, f):
    g = defaultdict(list)
    for l, r, c in edges:
        g[l].append((c, r))
    q, seen, mins = [(0, f, [])], set(), {f: 0}
    while q:
        (cost, v1, path) = heappop(q)
        if v1 not in seen:
            seen.add(v1)
            path = [v1] + path
            if v1 == t:
                return cost, path
            for c, v2 in g.get(v1, ()):
                if v2 in seen:
                    continue
                prev = mins.get(v2, None)
                next = cost + c
                if prev is None or next < prev:
                    mins[v2] = next
                    heappush(q, (next, v2, path))
    return float("inf"), []


def draw(value):
    # 初始化地图
    turtle.setup(width=953, height=759, startx=50, starty=30)
    turtle.clear()
    turtle.title("导航路线")
    # 图片URL
    url = 'https://startpage.zhuanjie.ltd/json/bigc.png'
    filename = os.path.basename(url)
    # 判断文件是否存在，如果不存在则下载
    if not os.path.isfile(os.path.join("./", filename)):
        try:
            print("地图下载中：")
            urlretrieve(url, './bigc.png', schedule)
        except os.error.HTTPError as e:
            print(e)
            print('\n' + url + '下载失败！' + '\n')
            tkinter.messagebox.showinfo('提示', '下载地图失败，请重试！')
        else:
            print("\n地图下载完成！")
    else:
        print("地图已经存在！")
    turtle.bgpic("bigc.png")
    turtle.pensize(15)
    turtle.color("#ff0000")
    turtle.hideturtle()
    for i in range(len(value[1]) - 1):
        move(value[1][i], value[1][i + 1])
    turtle.mainloop()
    # turtle.bye()


# 进度条迭代
def progressbar(cur, total=100):
    percent = '{:.2%}'.format(cur / total)
    sys.stdout.write('\r')
    sys.stdout.write("[%-100s] %s" % ('=' * int(cur), percent))
    sys.stdout.flush()


# 进度条
def schedule(blocknum, blocksize, totalsize):
    """
    blocknum:当前已经下载的块
    blocksize:每次传输的块大小
    totalsize:网页文件总大小
    """
    if totalsize == 0:
        percent = 0
    else:
        percent = blocknum * blocksize / totalsize
    if percent > 1.0:
        percent = 1.0
    percent = percent * 100
    progressbar(percent)


# 初始化
def init():
    # 特殊连线点
    parame = get_record('https://startpage.zhuanjie.ltd/json/parame.json')
    # 各个点在地图上的坐标
    pointin = get_record('https://startpage.zhuanjie.ltd/json/point.json')
    # 复选框的值
    valuesin = get_record('https://startpage.zhuanjie.ltd/json/values.json')
    # 根据两点距离将相邻的两个点存入matrix
    matrix = []
    for i in pointin:
        for j in pointin:
            if distence(i, j, parame, pointin) != 0 and distence(i, j, parame, pointin) != 1E100:
                matrix.append((i, j, distence(i, j, parame, pointin)))
    return pointin, valuesin, matrix


# 点击按钮运行部分
def calc(a, b):
    x = dijkstra(listview, a, b)
    print(x)
    try:
        draw(x)
    except turtle.Terminator:
        draw(x)


# 将json文件转化为变量
def get_record(url):
    resp = urllib.request.urlopen(url)
    ele_json = json.loads(resp.read())
    return ele_json


print("开始初始化")
point, values, listview = init()
root = Tk()
root.title('北京印刷学院导航系统')
root.geometry('320x50')
var1 = StringVar()
var2 = StringVar()
comb1 = Combobox(root, textvariable=var1, values=values, state='readonly')
comb2 = Combobox(root, textvariable=var2, values=values, state='readonly')
comb1.place(relx=0.1, rely=0.25, relwidth=0.2)
comb2.place(relx=0.4, rely=0.25, relwidth=0.2)
btn = Button(root, text="导航", command=lambda: calc(comb1.get(), comb2.get()))
btn.place(relx=0.7, rely=0.25, relwidth=0.2)
root.mainloop()

¶项目截图