將循環的輸出保存到文件

Question

我想將for循環的輸出（0,1,1,2,3）保存到文件中，但我的代碼只寫入循環的最後一個值（3）。我該如何解決它？

#!/usr/bin/python 

def fib(n): 
    a, b = 0, 1 
    for i in range(0, n): 
     a, b = b, a + b 
    return a 
for c in range(0, 5): 
    print(fib(c)) 
    file=open("fib.txt","w") 
    s = str(fib(c)) 
    file.write(s+"\n") 
# file.write("%s\n" % fib(c)) 
    file.close() 

Answer 1

試試這個。

def fib(n): 
    a, b = 0, 1 
    for i in range(0, n): 
     a, b = b, a + b 
    return a 
file=open("fib.txt", "a") 
for c in range(0, 5): 
    print(fib(c)) 
    s = str(fib(c)) 
    file.write(s + "\n") 
file.close() 

Answer 2

給一個嘗試的yield代替return

#!/usr/bin/python 

def fib(n): 
    a, b = 0, 1 
    for i in range(0, n): 
     a, b = b, a + b 
     yield a 
for c in range(0, 5): 
    print(fib(c)) 
    file=open("fib.txt","w") 
    for s in str(fib(c)): 
     file.write(s+"\n") 
    file.close() 

Answer 3

你可能想了解generators和context managers：

def fib(n): 
    a, b = 0, 1 
    for i in range(n): 
     a, b = b, a + b 
     yield a 

with open("fib.txt","w") as f: 
    for x in fib(5): 
     f.write(str(x) + '\n') 

Answer 4

那麼其不僅容易的，但更容易那麼容易...：P

使用相同代碼只需更改文件的模式，同時打開即...

file=open("fib.txt","w") #opens your file in write mode 

所以..它更改爲

file=open("fib.txt","a") #opens your file in append mode 

將在追加方式打開文件。