识别逗号之间的空格

Question

我需要确定数字和逗号之间是否有空格，那么该数字无效。因此，如果数字在逗号之间有超过或少于 2 个小数位和/或空格，那么它是无效的，但如果它在逗号之间没有空格并且有 2 个小数位，那么它是一个有效数字。这就是为什么第 1 行中的第一个数字是 VALID有两种方法，我更喜欢使用方法 2，但我认为如果我使用两种方法，它可能会帮助你们中的任何人添加#-----------Method 1------------------------------------------res = 0outfile = "output2.txt"baconFile = open(outfile,"wt")index = 0invalid_string = "INVALID"valid_string = "VALID"with open('file.txt') as file:    for line in file:        carrera = ''        index = index + 1        print("Line {}: ".format(index), end='')        baconFile.write("Line {}:  ".format(index))        number_list = line.strip().split(',')        for number in number_list:            if len(number.split('.')[-1]) == 2:                #res += 1##              print("VALID")                carrera = valid_string             if len(number.split('.')[-1]) != 2:                #res += 1                carrera = invalid_string            if len(number.split(',')[-1]) == " ":                         #checking for whitespace                 carrera = invalid_string            print (carrera, end=' ')            baconFile.write(carrera + " ")        print('\n', end='')        baconFile.write('\n')baconFile.close()#-----------Method 2------------------------------------------res = 0outfile = "output2.txt"baconFile = open(outfile,"wt")index = 0invalid_string = "INVALID"valid_string = "VALID"with open('file.txt') as file:这是我在 Text.file 中的数字列表：1,1.02, 123.00051.02, 1.02 , 1.02预期的：Line 1: INVALID VALID INVALIDLine 2: VALID INVALID INVALID (since there's spaces between the last number that's why it is INVALID) 实际的：Line 1: INVALID VALID INVALIDLine 2: VALID INVALID VALID

Answer 1

您可以拆分字符串,并根据字符串是否带有空格来确定字符串是有效还是无效

#Open the files

with open('file.txt') as fp:

    #Extract out non-empty lines from file

    lines = [line for line in fp.readlines() if line.strip()]

    res = []

    #Iterate over the lines

    for idx, line in enumerate(lines):

        #Number is valid if it doesn't start with a whitespace, has a decimal part and the decimal part is two digits long

        res = ['VALID' if not item.startswith(' ') and '.' in item and len(item.split('.')[1]) == 2 else 'INVALID' for item in line.split(',')]

        #Print the result

        print("Line {}: {}".format(idx+1, ' '.join(res)))

输出将是

Line 1: INVALID VALID INVALID

Line 2: VALID INVALID INVALID

Answer 2

尝试这个：

line="1,1.02, 123.0005"

reslt=line.split(",")

Res=" "

for i in reslt:

    if " "in i:

        line1="INVALID "

    else:

        line1="VALID "

    Res +="".join(line1)

print("line1:"+Res)

从文件中读取：

nbline

with open('file.txt') as f:

    for line in f.readlines():

        print(line)

        reslt=line.split(",")

        Res=" "

        for i in reslt:

            if " "in i:

                line1="INVALID "

            else:

                line1="VALID "

            Res +="".join(line1)

    nbline = nbline+1

    print("line {}:{}".format(nbline,Res))

输出：第 1 行：有效有效无效

Answer 3

使用decimal.Decimal对象，您可以检索指数，它以某种方式告诉您小数位数（请参阅文档）：

import decimal

o += " ".join(['INVALID' if x[0] == ' ' or decimal.Decimal(x).as_tuple().exponent != -2 else 'VALID' for x in line.split(',')])

输出

#with line = "1,1.02, 123.0005"

'Line 1: INVALID VALID INVALID'

#with line = "1.02, 1.02 , 1.02"

'Line 2: VALID INVALID INVALID'