How to read specify columns from file in GNU OCTAVE?

Question

In GNU OCTAVE, I have input file like this, and i have to read only first and second columns and store to variable. . This is only small part of my file. When so, i can not read whole file and cut a column that i need. I should read only what i need, to save a memory.

1 2 1 1015887601
1 3 1 1015887601
1 4 1 1015887601
1 5 1 1015887601
1 6 1 1015887601
1 7 1 1015887601
1 8 1 1015887601
1 9 1 1015887601
2 10 1 1015887601
2 11 1 1015887601
2 12 1 1015887601
3 13 1 1015887601
3 14 1 1015887601

Pokey McPokerson · Accepted Answer · 2014-06-12 06:59:42Z

1

Check out dlmread. Octave has the same function, it seems to do what you need.

Something like:

dlmread('yourfile.txt', ' ', 'A1..Bn') % replace n with the size of the file

edited Jun 12, 2014 at 6:59

answered Jun 11, 2014 at 14:33

Pokey McPokerson

7626 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

kkuilla Over a year ago

Or you can use the range parameter which is might be more appropriate. M = dlmread(filename, delimiter, range)

kkuilla Over a year ago

Why do you not add the link to Octave's dlmread() instead of Matlab's?

TNeykov Over a year ago

@Pokey McPokerson how can i get file size to replace n

Pokey McPokerson Over a year ago

Hi kkuilla, I used the Matlab link because it was very descriptive and had nice examples. The functions work exactly the same way as far as I can tell.

Pokey McPokerson Over a year ago

TNeykov, it seems like your data is fairly predictable? You could keep reading in blocks until you encounter a 0. Or if you're expecting 0s, you can set the "empty value" field to -1 (see the Octave function link in the updated answer).

Collectives™ on Stack Overflow

How to read specify columns from file in GNU OCTAVE?

1 Answer 1

5 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

5 Comments

Your Answer

Sign up or log in

Post as a guest

Related