Python语言程序设计课程案例 @ 北理工MOOC
Selected by liuyujie0136
（一）Python基本语法元素
#TempConvert.py
TempStr = input("请输入带有符号的温度值: ")
if TempStr[-1] in ['F', 'f']:
C = (eval(TempStr[0:-1]) - 32)/1.8
print("转换后的温度是{:.2f}C".format(C))
elif TempStr[-1] in ['C', 'c']:
F = 1.8*eval(TempStr[0:-1]) + 32
print("转换后的温度是{:.2f}F".format(F))
else:
print("输入格式错误")（二）Python基本图形绘制
#PythonDraw.py
import turtle
turtle.setup(650, 350, 200, 200)
turtle.penup()
turtle.fd(-250)
turtle.pendown()
turtle.pensize(25)
turtle.pencolor("purple")
turtle.seth(-40)
for i in range(4):
turtle.circle(40, 80)
turtle.circle(-40, 80)
turtle.circle(40, 80/2)
turtle.fd(40)
turtle.circle(16, 180)
turtle.fd(40 * 2/3)
turtle.done()（三）基本数据类型
天天向上的力量 第一问
#DayDayUpQ1.py
dayup = pow(1.001, 365)
daydown = pow(0.999, 365)
print("向上：{:.2f}，向下：{:.2f}".format(dayup, daydown))天天向上的力量 第二问
#DayDayUpQ2.py
dayfactor = 0.005
dayup = pow(1+dayfactor, 365)
daydown = pow(1-dayfactor, 365)
print("向上：{:.2f}，向下：{:.2f}".format(dayup, daydown))天天向上的力量 第三问
#DayDayUpQ3.py
dayup = 1.0
dayfactor = 0.01
for i in range(365):
if i % 7 in [6,0]:
dayup = dayup*(1-dayfactor)
else:
dayup = dayup*(1+dayfactor)
print("工作日的力量：{:.2f} ".format(dayup))天天向上的力量 第四问
#DayDayUpQ4.py
def dayUP(df):
dayup = 1
for i in range(365):
if i % 7 in [6,0]:
dayup = dayup*(1 - 0.01)
else:
dayup = dayup*(1 + df)
return dayup
dayfactor = 0.01
while dayUP(dayfactor) < 37.78:
dayfactor += 0.001
print("工作日的努力参数是：{:.3f} ".format(dayfactor))文本进度条 简单的开始
#TextProBarV1.py
import time
scale = 10
print("------执行开始------")
for i in range(scale+1):
a = '*' * i
b = '.' * (scale - i)
c = (i/scale)*100
print("{:^3.0f}%[{}->{}]".format(c,a,b))
time.sleep(0.1)
print("------执行结束------")文本进度条 单行动态刷新
#TextProBarV2.py
import time
for i in range(101):
print("\r{:3}%".format(i), end="")
time.sleep(0.1)文本进度条 实例完整效果
#TextProBarV3.py
import time
scale = 50
print("执行开始".center(scale//2, "-"))
start = time.perf_counter()
for i in range(scale+1):
a = '*' * i
b = '.' * (scale - i)
c = (i/scale)*100
dur = time.perf_counter() - start
print("\r{:^3.0f}%[{}->{}]{:.2f}s".format(c,a,b,dur),end='')
time.sleep(0.1)
print("\n"+"执行结束".center(scale//2,'-'))（四）程序的控制结构
BMI指数计算 版本1
#CalBMIv1.py
height, weight = eval(input("请输入身高(米)和体重(公斤)[逗号隔开]: "))
bmi = weight / pow(height, 2)
print("BMI 数值为：{:.2f}".format(bmi))
who = ""
if bmi < 18.5:
who = "偏瘦"
elif 18.5 <= bmi < 25:
who = "正常"
elif 25 <= bmi < 30:
who = "偏胖"
else:
who = "肥胖"
print("BMI 指标为:国际'{0}'".format(who))BMI指数计算 版本2
#CalBMIv2.py
height, weight = eval(input("请输入身高(米)和体重\(公斤)[逗号隔开]: "))
bmi = weight / pow(height, 2)
print("BMI 数值为：{:.2f}".format(bmi))
nat = ""
if bmi < 18.5:
nat = "偏瘦"
elif 18.5 <= bmi < 24:
nat = "正常"
elif 24 <= bmi < 28:
nat = "偏胖"
else:
nat = "肥胖"
print("BMI 指标为:国内'{0}'".format(nat))BMI指数计算 版本3
#CalBMIv3.py
height, weight = eval(input("请输入身高(米)和体重(公斤)[逗号隔开]: "))
bmi = weight / pow(height, 2)
print("BMI 数值为：{:.2f}".format(bmi))
who, nat = "", ""
if bmi < 18.5:
who, nat = "偏瘦", "偏瘦"
elif 18.5 <= bmi < 24:
who, nat = "正常", "正常"
elif 24 <= bmi < 25:
who, nat = "正常", "偏胖"
elif 25 <= bmi < 28:
who, nat = "偏胖", "偏胖"
elif 28 <= bmi < 30:
who, nat = "偏胖", "肥胖"
else:
who, nat = "肥胖", "肥胖"
print("BMI 指标为:国际'{0}', 国内'{1}'".format(who, nat))圆周率计算 公式法
#CalPiV1.py
pi = 0
N = 100
for k in range(N):
pi += 1/pow(16,k)*( \
4/(8*k+1) - 2/(8*k+4) - \
1/(8*k+5) - 1/(8*k+6) )
print("圆周率值是: {}".format(pi))圆周率计算 蒙特卡罗方法
#CalPiV2.py
from random import random
from time import perf_counter
DARTS = 1000*1000
hits = 0.0
start = perf_counter()
for i in range(1, DARTS+1):
x, y = random(), random()
dist = pow(x ** 2 + y ** 2, 0.5)
if dist <= 1.0:
hits = hits + 1
pi = 4 * (hits/DARTS)
print("圆周率值是: {}".format(pi))
print("运行时间是: {:.5f}s".format(perf_counter() - start))（五）函数和代码复用
七段数码管版本一
#SevenDigitsDrawV1.py
import turtle
def drawLine(draw): #绘制单段数码管
turtle.pendown() if draw else turtle.penup()
turtle.fd(40)
turtle.right(90)
def drawDigit(digit): #根据数字绘制七段数码管
drawLine(True) if digit in [2,3,4,5,6,8,9] else drawLine(False)
drawLine(True) if digit in [0,1,3,4,5,6,7,8,9] else drawLine(False)
drawLine(True) if digit in [0,2,3,5,6,8,9] else drawLine(False)
drawLine(True) if digit in [0,2,6,8] else drawLine(False)
turtle.left(90)
drawLine(True) if digit in [0,4,5,6,8,9] else drawLine(False)
drawLine(True) if digit in [0,2,3,5,6,7,8,9] else drawLine(False)
drawLine(True) if digit in [0,1,2,3,4,7,8,9] else drawLine(False)
turtle.left(180)
turtle.penup()
turtle.fd(20)
def drawDate(date): #获得要输出的数字
for i in date:
drawDigit(eval(i)) #通过eval()函数将数字变为整数
def main():
turtle.setup(800, 350, 200, 200)
turtle.penup()
turtle.fd(-300)
turtle.pensize(5)
drawDate('20181010')
turtle.hideturtle()
turtle.done()
main()七段数码管版本二
#SevenDigitsDrawV2.py
import turtle, time
def drawGap(): #绘制数码管间隔
turtle.penup()
turtle.fd(5)
def drawLine(draw): #绘制单段数码管
drawGap()
turtle.pendown() if draw else turtle.penup()
turtle.fd(40)
drawGap()
turtle.right(90)
def drawDigit(d): #根据数字绘制七段数码管
drawLine(True) if d in [2,3,4,5,6,8,9] else drawLine(False)
drawLine(True) if d in [0,1,3,4,5,6,7,8,9] else drawLine(False)
drawLine(True) if d in [0,2,3,5,6,8,9] else drawLine(False)
drawLine(True) if d in [0,2,6,8] else drawLine(False)
turtle.left(90)
drawLine(True) if d in [0,4,5,6,8,9] else drawLine(False)
drawLine(True) if d in [0,2,3,5,6,7,8,9] else drawLine(False)
drawLine(True) if d in [0,1,2,3,4,7,8,9] else drawLine(False)
turtle.left(180)
turtle.penup()
turtle.fd(20)
def drawDate(date):
turtle.pencolor("red")
for i in date:
if i == '-':
turtle.write('年',font=("Arial", 18, "normal"))
turtle.pencolor("green")
turtle.fd(40)
elif i == '=':
turtle.write('月',font=("Arial", 18, "normal"))
turtle.pencolor("blue")
turtle.fd(40)
elif i == '+':
turtle.write('日',font=("Arial", 18, "normal"))
else:
drawDigit(eval(i))
def main():
turtle.setup(800, 350, 200, 200)
turtle.penup()
turtle.fd(-350)
turtle.pensize(5)
# drawDate('2018-10=10+')
drawDate(time.strftime('%Y-%m=%d+',time.gmtime()))
turtle.hideturtle()
turtle.done()
main()科赫曲线绘制
#KochDrawV1.py
import turtle
def koch(size, n):
if n == 0:
turtle.fd(size)
else:
for angle in [0, 60, -120, 60]:
turtle.left(angle)
koch(size/3, n-1)
def main():
turtle.setup(800,400)
turtle.penup()
turtle.goto(-300, -50)
turtle.pendown()
turtle.pensize(2)
koch(600,3) # 0阶科赫曲线长度，阶数
turtle.hideturtle()
main()科赫雪花绘制
#KochDrawV2.py
import turtle
def koch(size, n):
if n == 0:
turtle.fd(size)
else:
for angle in [0, 60, -120, 60]:
turtle.left(angle)
koch(size/3, n-1)
def main():
turtle.setup(600,600)
turtle.penup()
turtle.goto(-200, 100)
turtle.pendown()
turtle.pensize(2)
level = 3 # 3阶科赫雪花，阶数
koch(400,level)
turtle.right(120)
koch(400,level)
turtle.right(120)
koch(400,level)
turtle.hideturtle()
main()（六）组合数据类型
基本统计值计算
#CalStatisticsV1.py
def getNum(): #获取用户不定长度的输入
nums = []
iNumStr = input("请输入数字(回车退出): ")
while iNumStr != "":
nums.append(eval(iNumStr))
iNumStr = input("请输入数字(回车退出): ")
return nums
def mean(numbers): #计算平均值
s = 0.0
for num in numbers:
s = s + num
return s / len(numbers)
def dev(numbers, mean): #计算方差
sdev = 0.0
for num in numbers:
sdev = sdev + (num - mean)**2
return pow(sdev / (len(numbers)-1), 0.5)
def median(numbers): #计算中位数
sorted(numbers)
size = len(numbers)
if size % 2 == 0:
med = (numbers[size//2-1] + numbers[size//2])/2
else:
med = numbers[size//2]
return med
n = getNum() #主体函数
m = mean(n)
print("平均值:{},方差:{:.2},中位数:{}.".format(m, dev(n,m),median(n)))文本词频统计
Hamlet词频统计
#CalHamletV1.py
def getText():
txt = open("hamlet.txt", "r").read()
txt = txt.lower()
for ch in '!"#$%&()*+,-./:;<=>?@[\\]^_‘{|}~':
txt = txt.replace(ch, " ") #将文本中特殊字符替换为空格
return txt
hamletTxt = getText()
words = hamletTxt.split()
counts = {}
for word in words:
counts[word] = counts.get(word,0) + 1
items = list(counts.items())
items.sort(key=lambda x:x[1], reverse=True)
for i in range(10):
word, count = items[i]
print ("{0:<10}{1:>5}".format(word, count))《三国演义》人物出场统计（上）
#CalThreeKingdomsV1.py
import jieba
txt = open("threekingdoms.txt", "r", encoding='utf-8').read()
words = jieba.lcut(txt)
counts = {}
for word in words:
if len(word) == 1:
continue
else:
counts[word] = counts.get(word,0) + 1
items = list(counts.items())
items.sort(key=lambda x:x[1], reverse=True)
for i in range(15):
word, count = items[i]
print ("{0:<10}{1:>5}".format(word, count))《三国演义》人物出场统计（下）
#CalThreeKingdomsV2.py
import jieba
excludes = {"将军","却说","荆州","二人","不可","不能","如此"}
txt = open("threekingdoms.txt", "r", encoding='utf-8').read()
words = jieba.lcut(txt)
counts = {}
for word in words:
if len(word) == 1:
continue
elif word == "诸葛亮" or word == "孔明曰":
rword = "孔明"
elif word == "关公" or word == "云长":
rword = "关羽"
elif word == "玄德" or word == "玄德曰":
rword = "刘备"
elif word == "孟德" or word == "丞相":
rword = "曹操"
else:
rword = word
counts[rword] = counts.get(rword,0) + 1
for word in excludes:
del counts[word]
items = list(counts.items())
items.sort(key=lambda x:x[1], reverse=True)
for i in range(10):
word, count = items[i]
print ("{0:<10}{1:>5}".format(word, count))（七）文件和数据格式化
自动轨迹规制
#AutoTraceDraw.py
import turtle as t
t.title('自动轨迹绘制')
t.setup(800, 600, 0, 0)
t.pencolor("red")
t.pensize(5)
#数据读取
datals = []
f = open("data.txt")
for line in f:
line = line.replace("\n","")
datals.append(list(map(eval, line.split(","))))
f.close()
#自动绘制
for i in range(len(datals)):
t.pencolor(datals[i][3],datals[i][4],datals[i][5])
t.fd(datals[i][0])
if datals[i][1]:
t.rt(datals[i][2])
else:
t.lt(datals[i][2])政府工作报告词云
常规矩形词云
#GovRptWordCloudv1.py
import jieba
import wordcloud
f = open("新时代中国特色社会主义.txt", "r", encoding="utf-8")
t = f.read()
f.close()
ls = jieba.lcut(t)
txt = " ".join(ls)
w = wordcloud.WordCloud( \
width = 1000, height = 700,\
background_color = "white",
font_path = "msyh.ttc"
)
w.generate(txt)
w.to_file("grwordcloud.png")不规则图形词云
#GovRptWordCloudv2.py
import jieba
import wordcloud
from scipy.misc import imread
mask = imread("chinamap.jpg")
excludes = { }
f = open("新时代中国特色社会主义.txt", "r", encoding="utf-8")
t = f.read()
f.close()
ls = jieba.lcut(t)
txt = " ".join(ls)
w = wordcloud.WordCloud(\
width = 1000, height = 700,\
background_color = "white",
font_path = "msyh.ttc", mask = mask
)
w.generate(txt)
w.to_file("grwordcloudm.png")（八）程序设计方法学
体育竞技分析
#MatchAnalysis.py
from random import random
def printIntro():
print("这个程序模拟两个选手A和B的某种竞技比赛")
print("程序运行需要A和B的能力值（以0到1之间的小数表示）")
def getInputs():
a = eval(input("请输入选手A的能力值(0-1): "))
b = eval(input("请输入选手B的能力值(0-1): "))
n = eval(input("模拟比赛的场次: "))
return a, b, n
def simNGames(n, probA, probB):
winsA, winsB = 0, 0
for i in range(n):
scoreA, scoreB = simOneGame(probA, probB)
if scoreA > scoreB:
winsA += 1
else:
winsB += 1
return winsA, winsB
def gameOver(a,b):
return a==15 or b==15
def simOneGame(probA, probB):
scoreA, scoreB = 0, 0
serving = "A"
while not gameOver(scoreA, scoreB):
if serving == "A":
if random() < probA:
scoreA += 1
else:
serving="B"
else:
if random() < probB:
scoreB += 1
else:
serving="A"
return scoreA, scoreB
def printSummary(winsA, winsB):
n = winsA + winsB
print("竞技分析开始，共模拟{}场比赛".format(n))
print("选手A获胜{}场比赛，占比{:0.1%}".format(winsA, winsA/n))
print("选手B获胜{}场比赛，占比{:0.1%}".format(winsB, winsB/n))
def main():
printIntro()
probA, probB, n = getInputs()
winsA, winsB = simNGames(n, probA, probB)
printSummary(winsA, winsB)
main()第三方库安装
#BatchInstall.py
import os
libs = {"numpy","matplotlib","pillow","sklearn","requests",\
"jieba","beautifulsoup4","wheel","networkx","sympy",\
"pyinstaller","django","flask","werobot","pyqt5",\
"pandas","pyopengl","pypdf2","docopt","pygame"}
try:
for lib in libs:
os.system("pip3 install "+lib)
print("Successful")
except:
print("Failed Somehow")（九）Python计算生态概览
霍兰德人格分析雷达图
#HollandRadarDraw
import numpy as np
import matplotlib.pyplot as plt
import matplotlib
matplotlib.rcParams['font.family']='SimHei'
radar_labels = np.array(['研究型(I)','艺术型(A)','社会型(S)',\
'企业型(E)','常规型(C)','现实型(R)']) #雷达标签
nAttr = 6
data = np.array([[0.40, 0.32, 0.35, 0.30, 0.30, 0.88],
[0.85, 0.35, 0.30, 0.40, 0.40, 0.30],
[0.43, 0.89, 0.30, 0.28, 0.22, 0.30],
[0.30, 0.25, 0.48, 0.85, 0.45, 0.40],
[0.20, 0.38, 0.87, 0.45, 0.32, 0.28],
[0.34, 0.31, 0.38, 0.40, 0.92, 0.28]]) #数据值
data_labels = ('艺术家', '实验员', '工程师', '推销员', '社会工作者','记事员')
angles = np.linspace(0, 2*np.pi, nAttr, endpoint=False)
data = np.concatenate((data, [data[0]]))
angles = np.concatenate((angles, [angles[0]]))
fig = plt.figure(facecolor="white")
plt.subplot(111, polar=True)
plt.plot(angles,data,'o-', linewidth=1, alpha=0.2)
plt.fill(angles,data, alpha=0.25)
plt.thetagrids(angles*180/np.pi, radar_labels)
plt.figtext(0.52, 0.95, '霍兰德人格分析', ha='center', size=20)
legend = plt.legend(data_labels, loc=(0.94, 0.80), labelspacing=0.1)
plt.setp(legend.get_texts(), fontsize='large')
plt.grid(True)
plt.savefig('holland_radar.jpg')
plt.show()玫瑰花绘制
#RoseDraw.py
import turtle as t
# 定义一个曲线绘制函数
def DegreeCurve(n, r, d=1):
for i in range(n):
t.left(d)
t.circle(r, abs(d))
# 初始位置设定
s = 0.2 # size
t.setup(450*5*s, 750*5*s)
t.pencolor("black")
t.fillcolor("red")
t.speed(100)
t.penup()
t.goto(0, 900*s)
t.pendown()
# 绘制花朵形状
t.begin_fill()
t.circle(200*s,30)
DegreeCurve(60, 50*s)
t.circle(200*s,30)
DegreeCurve(4, 100*s)
t.circle(200*s,50)
DegreeCurve(50, 50*s)
t.circle(350*s,65)
DegreeCurve(40, 70*s)
t.circle(150*s,50)
DegreeCurve(20, 50*s, -1)
t.circle(400*s,60)
DegreeCurve(18, 50*s)
t.fd(250*s)
t.right(150)
t.circle(-500*s,12)
t.left(140)
t.circle(550*s,110)
t.left(27)
t.circle(650*s,100)
t.left(130)
t.circle(-300*s,20)
t.right(123)
t.circle(220*s,57)
t.end_fill()
# 绘制花枝形状
t.left(120)
t.fd(280*s)
t.left(115)
t.circle(300*s,33)
t.left(180)
t.circle(-300*s,33)
DegreeCurve(70, 225*s, -1)
t.circle(350*s,104)
t.left(90)
t.circle(200*s,105)
t.circle(-500*s,63)
t.penup()
t.goto(170*s,-30*s)
t.pendown()
t.left(160)
DegreeCurve(20, 2500*s)
DegreeCurve(220, 250*s, -1)
# 绘制一个绿色叶子
t.fillcolor('green')
t.penup()
t.goto(670*s,-180*s)
t.pendown()
t.right(140)
t.begin_fill()
t.circle(300*s,120)
t.left(60)
t.circle(300*s,120)
t.end_fill()
t.penup()
t.goto(180*s,-550*s)
t.pendown()
t.right(85)
t.circle(600*s,40)
# 绘制另一个绿色叶子
t.penup()
t.goto(-150*s,-1000*s)
t.pendown()
t.begin_fill()
t.rt(120)
t.circle(300*s,115)
t.left(75)
t.circle(300*s,100)
t.end_fill()
t.penup()
t.goto(430*s,-1070*s)
t.pendown()
t.right(30)
t.circle(-600*s,35)
t.done()Last updated