中国大学MOOC課程「Python言語プログラミング」授業後練習(2週目)

中国大学MOOC課程「Python言語プログラミング」授業後練習(2週目)
1、蛇プログラムの描画:

import turtle

def drawSnake(rad,angle,len,neckrad):
    for i in range(len):  
        turtle.circle(rad,angle)  #     ，   
        turtle.circle(-rad,angle)
    turtle.circle(rad,angle/2)   
    turtle.fd(rad)
    turtle.circle(neckrad+1,180)  #     180 
    turtle.fd(rad*2/3)

def main():
    turtle.setup(1300,800,0,0)  #        
    pythonsize=3
    turtle.pensize(pythonsize)
    turtle.pencolor("blue")
    turtle.seth(-40) #       
    drawSnake(40,80,5,pythonsize/2)

main()

2、eval関数機能:文字列strを有効な式として評価し、計算結果を返す.
構文:eval(source[,globals[,locals]])->value
パラメータ:
source:Python式または関数compile()が返すコードオブジェクト
globals:オプション.ディクショナリでなければなりません
locals:オプション.任意mapオブジェクト

   list,tuple,dict string    。
#################################################
        
>>>a = "[[1,2], [3,4], [5,6], [7,8], [9,0]]"
>>>type(a)
'str'>
>>> b = eval(a)
>>> print b
[[1, 2], [3, 4], [5, 6], [7, 8], [9, 0]]
>>> type(b)
'list'>
#################################################
        
>>> a = "{1: 'a', 2: 'b'}"
>>> type(a)
'str'>
>>> b = eval(a)
>>> print b
{1: 'a', 2: 'b'}
>>> type(b)
'dict'>
#################################################
        
>>> a = "([1,2], [3,4], [5,6], [7,8], (9,0))"
>>> type(a)
'str'>
>>> b = eval(a)
>>> print b
([1, 2], [3, 4], [5, 6], [7, 8], (9, 0))
>>> type(b)
'tuple'>

3、カラーボアを描く

import turtle
import random
pencolors=['red','blue','yellow','black']
def drawSnake(rad,angle,len,neckrad):
    for i in range(len):
        turtle.circle(rad,angle)
        turtle.circle(-rad,angle)
        pencolor()
    turtle.circle(rad,angle/2)
    pencolor()
    turtle.fd(rad)
    turtle.circle(neckrad+1,180)
    pencolor()
    turtle.fd(rad*2/3)

def main():
    turtle.setup(1300,800,0,0)
    pythonsize=3
    turtle.pensize(pythonsize)
    pencolor()
    turtle.seth(-40)
    drawSnake(40,80,5,pythonsize/2)
def pencolor():
    turtle.pencolor(pencolors[random.randint(0,3)])

main()

異なる色を固定:
import turtle import random pencolors=[‘red’,’blue’,’yellow’,’black’] def drawSnake(rad,angle,len,neckrad): turtle.pencolor(pencolors[3]) for i in range(len): turtle.circle(rad,angle) turtle.circle(-rad,angle) turtle.pencolor(pencolors[1]) turtle.circle(rad,angle/2) turtle.pencolor(pencolors[0]) turtle.fd(rad) turtle.circle(neckrad+1,180) turtle.fd(rad*2/3)
def main(): turtle.setup(1300,800,0,0) pythonsize=30 turtle.pensize(pythonsize) turtle.seth(-40) drawSnake(40,80,5,pythonsize/2)
main()

4、    
5、       

import turtle
for i in range(3): turtle.fd(50) turtle.left(120)
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