Indexing all the row data for each column

Hi everyone,

For example, if I had a matrix with 10 rows but variable column lengths for each row how would I iterate "for all row datapoints within each column"?

Right now using A(1:end,1:end) returns the entire matrix, but I would need to isolate each column of data.

Thank you in advance

[Scott MacKenzie]

In MATLAB it is not possible to have "a matrix with 10 rows but variable column lengths", so you might want to re-think your question.

[Rik]

You can't have non-rectangular arrays in Matlab.

You can approximately get the same effect by using a cell array, or by padding with NaN. The most optimal strategy will depend on what you want to do.

[Vin]

Sorry, I will try to be more clear.

The matrix would be 10x15 (15 being the most amount of actual data within a column), all other columns within the matrix that have less than 15 rows are padded with NaN.

Each column of data represents a waveform. My intentions would be to normalize all 10 columns of data from 0-100% to make all columns the same length.

Answer 1

[millercommamatt]

For a 2D matrix, you can access a row as follows:

% Matlab indexing is row major
% return single row of matrix A
A(1,:)
A(2,:)
A(end,:)

%return single column of A
A(:,1)
A(:,2)
A(:,end)