How to read a CSV file into vector matrix of 2 column?

I have 2 CSV files which have multiple values. I want to create a vector matrix, which could be of multiple row but 2 column. Index 1 of column 1 will hold first 1000 values from a CSV file1. Similarly, index 1 of column 2 will hold first 1000 values from a CSV file2. And this process will continue until all the data is fetched from both CSV files.

[Matt J]

Index 1 of column 1 will hold first 1000 values from a CSV file1

Index i of any matlab numeric array cannot hold a non-scalar. However, I wonder if that is what you really mean.

[hsnal]

I mean I want the first 1000 values, which is flaoting point data, to be saved at the very first index of column 1 in vector matrix. Similarly, the column 2 will will have values in same manner but from different csv file.

[Stephen23]

You could use a cell array and indexing:

https://www.mathworks.com/help/matlab/matlab_prog/access-data-in-a-cell-array.html

Answer 1

[Rishi]

Hi hsnal,

I understand from your query that you want to read data from two CSV files into a vector matrix such that the first column of the matrix contains the data in chunks of 1000 values from the first CSV file, and the second column contains the same from the second CSV file.

Here is a sample code to help you do the same:

csv_file1 = 'file1.csv';
csv_file2 = 'file2.csv';

% Read the data from the CSV files, assuming the data is numeric
data1 = readmatrix(csv_file1); 
data2 = readmatrix(csv_file2); 

num_chunks = max(ceil(length(data1)/1000), ceil(length(data2)/1000));

vector_matrix = cell(num_chunks, 2); 

for i = 1:num_chunks
    % Calculate the start and end indices for the current chunk
    start_idx = (i - 1) * 1000 + 1;
    end_idx = min(i * 1000, length(data1));
    
    % Assign the chunk of 1000 values from each file to the matrix
    vector_matrix{i, 1} = data1(start_idx:end_idx);
    
    % Check if the second file has enough data; if not, adjust the end index
    end_idx = min(i * 1000, length(data2));
    vector_matrix{i, 2} = data2(start_idx:end_idx);
end

You can learn more about 'readmatrix' from the below documentation:

https://www.mathworks.com/help/matlab/ref/readmatrix.html

You can also use 'readtable' or 'csvread' to get the data from CSV files, and you can learn more about them here:

https://www.mathworks.com/help/matlab/ref/readtable.html

https://www.mathworks.com/help/matlab/ref/csvread.html

Hope this helps!