When reading in a txt matrix, how can i skip first column
Question: I have a file that looks like this:

    
    
        1   2   3   4   5   6   7
    1   0   1   1   1   1   1   1
    2   0   0   1   1   1   1   1
    3   0   0   0   1   1   1   1
    4   0   0   0   0   1   1   1
    5   0   0   0   0   0   1   1
    6   0   0   0   0   0   0   1
    7   0   0   0   0   0   0   0
    

I want to read in only the 1 and 0 and ignore the top header row and the row
name (the first column).

So far I have the header line all set, but how can I skip the skip column. My
code so far

    
    
    with open('file') as f:
        next(f) #skips header row
        content = [x.strip('\n') for x in f.readlines()]
    

I'm trying to use only base python and no libraries.


Answer: Use a simple indexing:

    
    
    with open('file') as f:
        next(f)
        content = [x.strip().split()[1:] for x in f]
    

This will give you the splitted zero and ones as a nested list.

If you don't want to split the lines you can still use indexing in order to
remove the first character.

    
    
    content = [x[1:].strip() for x in f]
    

Or as a Numpythonic approach you can use `loadtxt()` function:

    
    
    >>> import numpy as np
    >>> form io import StringIO
    >>> np.loadtxt(StringIO(my_string), skiprows=1)[:,1:]
    array([[ 0.,  1.,  1.,  1.,  1.,  1.,  1.],
           [ 0.,  0.,  1.,  1.,  1.,  1.,  1.],
           [ 0.,  0.,  0.,  1.,  1.,  1.,  1.],
           [ 0.,  0.,  0.,  0.,  1.,  1.,  1.],
           [ 0.,  0.,  0.,  0.,  0.,  1.,  1.],
           [ 0.,  0.,  0.,  0.,  0.,  0.,  1.],
           [ 0.,  0.,  0.,  0.,  0.,  0.,  0.]])
    

