首页 > 解决方案 > 如何获得重复一次的数字?

问题描述

我有一个包含很多数字的文件:

0.98
0.23
0.10
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
10.3
11.9
0.56
...

我想打印数字 0 连续重复 10 次的行数(至少)。考虑到上面的输入,输出将是:4(对于第 4 行,因为 0 es 连续重复了 10 次)。文件 list.txt 是一个巨大的文件。我是 Python 新手。如何删除以下脚本中的错误:

import ast
values = open("list.txt","r")
values = list(map(int, ast.literal_eval(values.read().strip())))
count=0
length=""
if len(values)>1:
    for i in range(1,len(values)):
       if values[i-1]==values[i]:
          count+=1
       else :
           length += values[i-1]+" repeats "+str(count)+", "
           count=1
    length += ("and "+values[i]+" repeats "+str(count))
else:
    i=0
    length += ("and "+values[i]+" repeats "+str(count))
print (length)

标签: pythonfileiterationprocessing-efficiency

解决方案


逐行读取和评估文件。如果找到模式,则循环中断,停止读取文件

import ast
count = 0
lineNb = -1
found = False # False by default
with open("list.txt") as f:
    for i,line in enumerate(f): # loop over lines, one-by-one
        value = ast.literal_eval(line)
        if value == 0:
            if count == 0: # first occurrence
                lineNb = i # set potential lineNb
            count += 1     # increment counter
            if count == 10: # desired condition
                found = True # now we know we have found the pattern
                break        # break the for loop
        else: # not 0
            count = 0 # reset counter

print(found,lineNb) # (True,3) # lineNb is zero-based, 3 = 4th line

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