如何用括號將列表打印到python中的文件中

Question

我想將輸出列表打印到文件中作爲下面的輸出，但它不斷給我錯誤。

樣品輸入

0 
2 
5 
12 
32 
64 
241 

樣品輸入

[1, 0] 
[0, 2] 
[-4, -4] 
[-64, 0] 
[65536, 0] 
[4294967296, 0] 
[1329227995784915872903807060280344576, 1329227995784915872903807060280344576] 

這裏position.dat的內容是我的代碼：

infile = open("position.dat", "w") 
def B(n): 
    direction=[[1,0],[0,1],[-1,0],[0,-1]] #right, up, left, down 
    start=[0,0] 
    x=start[0] 
    y=start[1]  
    if n>50000: 
     return "Do not enter input that is larger than 50000" 
    elif n==0: #base case 
     return [1, 0] 
    elif n==1: 
     return [1, 1] 

    elif n%2==0 and n%4!=0: #digit start from n=2 and every 4th n digit 
     x=0   # start from second digit (n) x=0 for every 4th digit 
     y=((-4)**(n//4))*2 


    elif n%4==0:  #print out every 4 digits n 
     y=0 #every 4digit of y will be 0 start from n=0 
     x=(-4)**(n//4) #the pattern for every 4th digits 

    elif n>3 and n%2 !=0 and n%4==1: #start from n=1 and for every 4th digit 
     x=(-4)**(n//4) 
     y=(-4)**(n//4) 

    elif n%4==3 and n%2 != 0: #start from n=3 
     y=((-4)**(n//4))*2 
     x=((-4)**(n//4))*-2 
    return [int(x),int(y)]  #return result 


print(B(0)) # print the input onto python shell 
print(B(2)) 
print(B(5)) 
print(B(12)) 
print(B(32)) 
print(B(64)) 
print(B(241)) 
print(B(1251)) 
#Please also input the integers below for printing it on the the file 

infile.write(B(0)+'\n') # these keep giving me error 
infile.write(B(2)+'\n') 



infile.close() 

是否可以打印清單到與文件托架？

Answer 1

您不能直接使用write編寫列表。你可以，但是，生成原始字符串：

s0 = "[" + ", ".join([str(x) for x in B(0)]) + "]" 
infile.write(s0 + "\n") 

Answer 2

您可以使用類似的東西：

with open ("temp.txt","wt") as fh: 
    fh.write("%s\n" % str([0,1])) 

• 使用格式化原語
• 明確地定義你的元素轉換爲字符串

或者，使用個人格式：

fh.write("[%s]\n" %(','.join(map (str,B(0)))) 

Answer 3

list的__str__方法可以爲您做到這一點。即使用

infile.write(str(B(0)) + '\n') 
infile.write(str(B(2)) + '\n')