如何在不四舍五入的情况下获得小数值

Question

如何将两个数字相加并在最终答案中保留它们的小数位？下面是执行此操作的代码，但它不起作用。

import re
cnt=0
s=0
l1= []
with open('C://Users/S/Documents/ok5.txt') as f:
    for i in f:
        if i.startswith('X-DSPAM-Confidence:'):
            x = re.findall('\d*?\.\d+',i)
            l1.append(x)
            cnt+=1

for i in range(0,len(l1)):
    j = float(i)
    s += j

print(l1)    
print(s)

我得到的输出是：

[['0.5454'], ['0.5677']]
1.0

但是，当我尝试下面的简单代码时，它给出了正确的答案：

a = 0.5454
b = 0.5677
c = float(a+b)
print(c)

这个输出是：

1.1131

Answer 1

我想你想这样做：

import re
cnt=0
s=0
l1= []
with open('C://Users/S/Documents/ok5.txt') as f:
    for i in f:
        if i.startswith('X-DSPAM-Confidence:'):
            x = re.findall('\d*?\.\d+',i)
            l1.append(x)
            s += float(x[0]) # You could just add it here, which improves time complexity
            cnt+=1
print(l1)    
print(s)

如何在不四舍五入的情况下获得小数值

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