MATLAB: How to read CSV file and save the result to another CSV file

csvimage analysismatrixmatrix arraymatrix manipulation

Hello.

I have several CSV files.

After processing each CSV file, I want to save each CSV file to other name using for loop.

The names of input file are different (bend1.csv, walk2.csv, jogging2.csv, ….)

clear all
close all
X = csvread('bend1.csv');
X = X(:,1:28);
data = X';
% After processing......
% I want to each Y matrix to CSV files
Y = Phi_NuMax * X';
csvwrite('/result/bend1.csv', Y);

Best Answer

a simple structure:

outDir = yourDestination.
allCsvFiles = dir(fullfile(yourDirectory, '.*csv'));
for iA = 1:length(allCsvFiles)
    curFile = allCsvFiles(iA).name;
    
    yourTable = readtable(fullfile(yourDirectory, curFile));
    % your process
    
    writetable(fullfile(outDir, curFile), yourTable);
end

Related Solutions

MATLAB: Unable to perform assignment because brace indexing is not supported for variables of this type.

At the bottom of your loop you have

    data = data{i};

That replaces the cell array data that contains the cell with framegray{1}', with the contents of that entry, so instead of data being a cell array with framegray{1}' inside it, data would become the contents directly, framegray{1}' not inside a cell array. Then in the second iteration of the loop when you go to assign to data{2} then data is not a cell array and you are not permitted to do that.

You should be asking yourself why you are doing the

    data = data{i};

MATLAB: How to find the minimum number of row and column and concatenate to a matrix

Don't you need the minimum dimension in order to concatenate? In other words, you need to find the max dimensions. Untested code:

minRequiredRows = 0;
minRequiredColumns = 0;
for k = 1 : length(Phi_NuMax)
    thisMatrix = Phi_NuMax{k};
    [thisRows, thisColumns] = size(thisMatrix);
    fprintf('Cell #%d has %d rows and %d columns.\n', k, thisRows, thisColumns);
    % Find out how wide the matrix will need to be if they are all stacked on top of one another.
    minRequiredColumns = max(minRequiredColumns, thisColumns);
    % Sum up how many rows we'll need to hold all of them vertically.
    minRequiredRows = minRequiredRows + thisRows; 
end
fprintf('At a minimum, you will require %d rows and %d columns.\n', k, minRequiredRows, minRequiredColumns);
% Now instantiate a matrix for all the individual matrices stitched together vertically.
allMatrixes = zeros(minRequiredRows, minRequiredColumns);
% Now concatenate by inserting the cell into all Matrixes at the appropriate row number.
currentRow = 1;
for k = 1 : length(Phi_NuMax)
    thisMatrix = Phi_NuMax{k};
    [thisRows, thisColumns] = size(thisMatrix);
    fprintf('Inserting cell #%d with %d rows and %d columns.\n', k, thisRows, thisColumns);
    allMatrixes(currentRow : currentRow + thisRows - 1, 1:thisRows) = thisMatrix;
    % Move the pointer to the next place where we will insert the next matrix.
    currentRow = currentRow + thisRows;
end

Best Answer

Related Solutions

MATLAB: Unable to perform assignment because brace indexing is not supported for variables of this type.

MATLAB: How to find the minimum number of row and column and concatenate to a matrix

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