Opening A Space(?) Delimited Text File In Python 2.7?

I have what I think is a space delimited text file that I would like to open and copy some of the data to lists (Python 2.7). This is a snippet of the data file: 0.000000

Solution 1:

One alternative is to take advantage of the built-in str.split():

a, b, c, d, e = zip(*((map(float, line.split()) for line in open('data_file.txt'))))

Solution 2:

The problem is the multiple spaces between fields (columns).

CSV stands for comma-separated values. Imagine for a second that you are using commas instead of spaces. Line 1 in your file would then look like:

,,,,0.000000,,,,,,,11.00,,,,,,737.09,,,,,,,1.00,,,,,1116.00

So, the CSV reader sees more than 5 fields (columns) in that row.

You have two options:

1. Switch to using single space separators
2. Use a simple split() to deal with multiple whitespace:

:

 listb = []
 listd = []
 with open('text', 'r') as file:
    for row in file:
        a, b, c, d, e = row.split()
        listb.append(int(b))
        listd.append(int(d))

P.S: Once this part is working, you will run into a problem calling int() on strings like "11.00" which aren't really integers. So I recommend using something like:

int(float(b))

Solution 3:

f=open("input.txt",'r')
x=f.readlines()
list1=[]
list2=[]
import re
for line in x:
  pattern=re.compile(r"(\d+)(?=\.)")
  li=pattern.findall(line)
  list1.append(li[1])
  list2.append(li[3])

You can use this if you only want to capture integersand not floats.

Solution 4:

You can find all values you need, using regexp

import re

list_b = []
list_d = []

with open('C://data_file.txt', 'r') as f:
    for line in f:
        list_line = re.findall(r"[\d.\d+']+", line)
        list_b.append(float(list_line[1])) #appends second column
        list_d.append(float(list_line[3])) #appends fourth column

print list_b
print list_d