Reading csv from the second line and creating output

I want from a csv archive to read only one column. The problem is that I want to read this column from the second line and by using these commands:

[d1,tex]= xlsread(filename1);

name=tex(:,4)

it's reading from the first line.

Also, I would like to create a matrix that will inclue two columns that have come from commants (equations etc) in my Matlab code.

Answer 1

[Star Strider]

Try this:

name = tex(2:end,4)

‘Also, I would like to create a matrix that will inclue two columns that have come from commants (equations etc) in my Matlab code.’

Please provide details.

[Star Strider]

Ravnalis Michael’s Answer moved here:

Look, I would like to make a matrix which will include 2 columns . The first column will include the "name" and the other one will include onether result, for example name2=d1(:,7); (d1 is an input archive). In conlusion, one matrix with the results

[Star Strider]

Create a cell array or a table, depending on what you want to do.

Example (cell array):

M = {tex(2:end,4), d1(2:end,7)}

See the documentation on Cell Arrays for details.

[Walter Roberson]

The name sounds like character, but the other value might be numeric. You would need to use a cell array or a table() object.

You should probably be considering readtable()

[Star Strider]

Ravnalis Michael’s Answer moved here:

ok , it works but i have one last problem about the export of my results . I want to export the matrix "M = {tex(2:end,4), d1(2:end,7)}" into a txt. I am using these commants:

fid = fopen('final.txt','wt');

fprintf(fid,'%.6f\n',M);

fclose(fid);

but it not works...

Do you have any idea why ?

[Star Strider]

It is most likely not working because you are attempting to write a cell array containing character or string variables and numerical variables using fprintf.

If you have R2013b or later, use the cell2table function, then the writetable function.

Example:

TM = cell2table(M);
writetable(TM, 'final.txt');

I have not tested this, so I am listing it as UNTESTED CODE. It should work.

[Walter Roberson]

What datatype is tex? Is it cell array of character vectors, or is it string() objects?

[Ivan Mich]

Walter Roberson, It is cell array

[Star Strider]

@Ravnalis Michael — Are you still having problems? If so, what is wrong?

[Ivan Mich]

@Star Strider the problem is that in the 'final.txt' archive has not the format that i want. Basically the format consist of two line, where first row has this format:

M1,M2_ 1,M2_ 2,M2_ 3,M2_ 4,M2_ .........

and the second line has this format:

1, 2, 3.

I would like to have vertical format and in the first column to see the full name of the cells, and not M1,M2_ 1,M2_ 2,M2_ 3,M2_ 4,M2_ .........

[Walter Roberson]

M = [tex(2:end,1), num2cell(d1(2:end,7))].';  %transpose important 

fprintf(fid,'%15s %.6f\n',M{:} );

Adjust the width of the string as needed.

[Ivan Mich]

@Walter Roberson Thank a lot, now it works exactly as I want !!!

[Star Strider]

You most likely have to transpose your data to column vectors before you put them in your cell array (or table).

I have no ideq what you are doing with your code. I cannot determine what the problem is and fix it without your data and a description of what you want.

This example code does what you say you want:

M = {'abc' 2; 'def', 3; 'ghi' 42};
TM = cell2table(M);

producing:

TM =

  3×2 table

     M1      M2
    _____    __

    'abc'     2
    'def'     3
    'ghi'    42

This version of my code:

names = {'abc', 'def', 'ghi'};
d1 = [1, 2, 42];
TM = table(names', d1')

(note the transpose operator (')) produces the same result:

TM =

  3×2 table

    Var1     Var2
    _____    ____

    'abc'      1 
    'def'      2 
    'ghi'     42 

You may have to use the table function rather than cell2table. I have no idea because I can’t see your data or your code.

[Star Strider]

Did the approach in my previous Comment work, or are you still having problems?

[Ivan Mich]

Star Strider everything it's ok! Thank you for helping me !!

[Star Strider]

My pleasure!

If my Answer helped you solve your problem, please Accept it!