Separating a colymn into two columns (.txt file)

Hello,

I would like to separate a column into two different columns from a .txt file in Matlab. I used these commands:

t=readtable('file.txt','Delimiter','\t','HeaderLines',1)

and the results of these commands are in the pictures. Finally, I mean that i would like to separate line 11 into two vertical columns.

Which command should I use?

Answer 1

[David K.]

I would do it like this:

%t = your table;
dataCell = table2cell(t); % convert to cells
dataCell = dataCell(11:end); % remove unneccessary text
cellNums = cellfun(@str2num,dataCell,'UniformOutput',0); % apply str to num on all the data
output = cell2mat(cellNums); % convert to matrix with 2 columns

*Edit: fixed a few things

[Ivan Mich]

I used these commands and command window shows:

Error using cellfun

Input #2 expected to be a cell array, was char instead.

What should I do?

[Ivan Mich]

Error in line 17

cellNums = cellfun(@str2num,dataCell,'UniformOutput',0); % apply str to num on all the

data

[David K.]

hm, that is unexpected. Could you post your actual data as like a mat file or something so I can more thoroughly test what my answer?

[Ivan Mich]

Well, my data are a .txt file which has this format:

[David K.]

Alright, I fixed my answer it should work now.

[Ivan Mich]

It works ,Thanks a lot !!!

[Ivan Mich]

Excuse me but I have one more question,

If I had a .txt file (see image) like this and I would like to separate it into columns, like the previous one, which command should I use ?

I believe that the problem is in command

output = cell2mat(cellNums); % convert to matrix with 2 columns

(I mean I would like to separate my file in 8 columns).

[David K.]

One issue I see is that minY and maxY are only on 1 row so it creates issues with there being differently sized cells that cannot be converted to a matrix.

To fix that I would pad the cells so that they are all the same size. I am going to do that by padding each cell with zeros.

cellNums = cellfun(@(x)[x,zeros(1,8-length(x))],cellNums,'UniformOutput',0)

This will make it so that every cell has 8 columns and can then be put into the cell2mat function.

[Ivan Mich]

Ok, one last question please. If i would want to "pick" from this .txt file (see image up) only the number of 9th line which command would help me to make it?

[David K.]

Personally, I'm not great at reading in and out files all that well. I think there are some commands that let you set where you are reading in from and how how much to read in. But since the matrix is all ready read into matlab I would just use the matrix index to choose the value you need.

If you really only want to get one value then I would check out fseek and other f- commands.