using numpy to import multiple text files

Question

I've been importing multiple txt files and using them to create plots. The code is the same as before but it isn't seeming to work this time. I've taken it back to basics and I have no idea what's going wrong.

import numpy    
close('all')    
data = []
pixels = []

for i in range(0,92):    
    data.append(genfromtxt('filename_'+str(i+1)+'.txt', usecols=4))
    pixels.append(genfromtxt('filename_'+str(i+1)+'.txt', usecols=5))

I only need the columns stated in the loop as the txt files have multiple values. This returns:

    raise ValueError(errmsg)
ValueError: Some errors were detected !
    Line #1 (got 2 columns instead of 1)
    Line #3 (got 1 columns instead of 1)
    Line #5 (got 3 columns instead of 1)
    Line #6 (got 3 columns instead of 1)
    Line #8 (got 4 columns instead of 1)
    Line #10 (got 2 columns instead of 1)
    Line #11 (got 2 columns instead of 1)
    Line #12 (got 1 columns instead of 1)
    Line #35 (got 1 columns instead of 1)

Any help, would be fantastic!

Check your txt files. Looks like the problem might be in them — Sleepyhead, Mar 14 '14 at 19:09
Thank you. Turns out I'd managed to corrupt one of the files.. — GGoodfellow, Mar 17 '14 at 13:16

score 0 · Answer 1 · answered Mar 14 '14 at 20:06

The problem is how you are passing the usecols parameter, it must be a sequence (list or tuple, for example), with 0 being the first column. Perhaps you wanted this:

for i in range(0,92):    
    data.append(genfromtxt('filename_'+str(i+1)+'.txt', usecols=(0,1,2,3)))
    pixels.append(genfromtxt('filename_'+str(i+1)+'.txt', usecols=(0,1,2,3,4)))

using numpy to import multiple text files

1 Answers1