csv.reader problem tab-delimiter - newbie

[hidding]

Hi all,

I use python 2.5 and want to read in a simple 5-columned, tab-
delimited ascii file "dummy.txt" such as as

1 2 3.0 4 5.6
4 6 77 8.2 19

I do

import csv
asciireader = csv.reader(open('dummy.txt'), delimiter='\t')

array1 = []
for entry in asciireader:
array1.append( entry )

however when I then

print array1

then the array does only have two elements [1 2 3.0 4 5.6]
and [4 6 77 8.2 19]. The tab-delimiter seems to have been
totally ignored! This is bad because I want to do some maths with the
numbers from the file later (after converting them into floats).

Can someone help?

Best regards,

Bernhard

 

[George Sakkis]

Hi all,

I use python 2.5 and want to read in a simple 5-columned, tab-
delimited ascii file "dummy.txt" such as as

1  2    3.0    4     5.6
4  6    77     8.2  19

I do

import csv
asciireader = csv.reader(open('dummy.txt'), delimiter='\t')

array1 = []
for entry in asciireader:
 array1.append( entry )

however when I then

print array1

then the array does only have two elements [1  2    3.0    4     5.6]
and [4  6    77     8.2  19]. The tab-delimiter seems to have been
totally ignored! This is bad because I want to do some maths with the
numbers from the file later (after converting them into floats).

Can someone help?

Best regards,

Bernhard

Most likely the file is not tab delimited. If you used an editor to
produce dummy.txt, check whether it uses soft tabs and disable it
temporarily.

HTH,
George

 

[hidding]

Most likely the file is not tab delimited. If you used an editor to
produce dummy.txt, check whether it uses soft tabs and disable it
temporarily.

HTH,
George

Most likely the file is not tab delimited. If you used an editor to
produce dummy.txt, check whether it uses soft tabs and disable it
temporarily.

HTH,
George

grrr thanks George, thanks Daniel, that's it. Works fine with real
tabs. Now this brings me to a follow-up: I have not prepared the input
ascii file, I just got if for post-processing (23 MB). Now it seems
that I would have to replace all series of spaces in this file with
real tabs at first.. How would you do that? Are there text editors
capable of doing this?

Best regards,

Bernhard

 

[Clovis Fabricio]

grrr thanks George, thanks Daniel, that's it. Works fine with real
tabs. Now this brings me to a follow-up: I have not prepared the input
ascii file, I just got if for post-processing (23 MB). Now it seems
that I would have to replace all series of spaces in this file with
real tabs at first.. How would you do that? Are there text editors
capable of doing this?

If the file you got isn't really tab delimited, you shouldn't convert
it to a tab delimited file before processing.

Just process it as it is, a multiple-space-delimited file.

f = open('file.txt')
for line in f:
line = line.strip().split()
# do whatever with data
print line
f.close()

Clóvis

 

[George Sakkis]

grrr thanks George, thanks Daniel, that's it. Works fine with real
tabs. Now this brings me to a follow-up: I have not prepared the input
ascii file, I just got if for post-processing (23 MB). Now it seems
that I would have to replace all series of spaces in this file with
real tabs at first.. How would you do that? Are there text editors
capable of doing this?

If your file consists of numbers only, you don't even need csv; you
can read the whole file and convert it to floats in a single readable
line:

data = [map(float, line.split()) for line in open('dummy.txt')]

HTH,
George