如何从文件的每一行提取字符和数字？

Question

I tried to extract first character,second number and third character from each line of file and storing into three variables called FirstChar,SecondNum,ThirdChar.

Input file (MultiPointMutation.txt):

P1T,C11F,E13T
L7A
E2W

Expected output:

FirstChar="PCELE"
SecondNum="1 11 13 7 2"
ThirdChar="TFTAW"

My code:

 import re 
 import itertools
 ns=map(lambda x:x.strip(),open('MultiplePointMutation.txt','r').readlines())#reading  file
 for line in ns:
         second="".join(re.findall(r'\d+',line))#extract second position numbers
         print second # print second nums
         char="".join(re.findall(r'[a-zA-Z]',line))#Extract all characters
         c=str(char.rstrip())
         First=0
         Third=1
         for index in range(len(c)):
                 if index==First:
                         FC=c[index]#here i got all first characters
                         print FC
                         First=First+2
                 if index==Third:
                         TC=c[index]
                         print TC
                         Third=Third+2#here i got all third characters

OUTPUT: Here I got FirstCharacter and ThirdCharacter exactly correct

FirstChar:
          P
          C
          E
          L
          E
ThirdChar:
          T
          F
          T
          A
          W

but the problem is in getting SecondNum:

           SecondNum:
           11113
           7
           2

I want to extract numbers as follows:

          1
          11
          13
          7
          2

NOTE: Here, I don't want to print one by one. I want read this SecondNum variable values one by one for latter use.

Answer 1

for secondNum you can simply modify the line:

second="".join(re.findall(r'\d+',line))#extract second position numbers

to

second="\n".join(re.findall(r'\d+',line))#extract second position numbers

but I think your first and third char doesnt work correctly. From the first output you want to receive you should have something like this:

 import re

 x= """P1T,C11F,E13T
 L7A
 E2W"""

 secondNum = []
 firstChar = []
 thirdChar = []
 for line in x.split('\n'):

      [secondNum.append(a) for a in re.findall('\d+',line)]

      [firstChar.append(a) for a in re.findall('(?:^|,)([a-zA-Z])',line)]
      # this is an inline for loop which takes each element returned from re.findall  
      # and appends it to the firstChar Array
      # the regex searchs for the start of the string (^) or a comma(,) and this is a 
      # non capturing group (starting with (?:  meaning that the result of this group 
      # is not considered for the returned result and finally capture 1 character 
      # [a-zA-Z] behind the comma or the start which should be the first character

      [thirdChar.append(a) for a in re.findall('(?:^\w\d+|,\w\d+)([a-zA-Z])',line)
      # the third char works quite similar, but the non capturing group searchs for a 
      # comma or start of the string again followed by 1 char and at least one number 
      # (\d+) after this number there should be the third character which is in the 
      # captured group again

 print "firstChar=\""+str(firstChar)+"\""
 print "secondNum=\""+str(secondNum)+"\""
 print "thirdChar=\""+str(thirdChar)+"\"" 

But your third character is the third with the numbers for L7A (where you want to have A) but it is also the forth for P1TQ (where you want to have Q)