How can I use Import Data function on multiple files? (Creating variables from multiple files in a loop?)

Hi MATLAB Central,

I'd like to use the Import Data quickbutton to generate a function which extracts data from multiple files.

To generate the IMPORTDATA function for a certain file, I start generating the script by highlighting the data, then clicking 'Import Selection'>> 'Generate Function'.

The code below is what I generate for a single import, here on file '7Feb14_Alg_Only_136p_1.txt'. It will store two columns of data with the variables 'Henckystrain' and 'EngineeringStress'.

I'd like this to operate on multiple files within a folder and change the variables continuously to reflect the file name;

e.g. Here variables would be saved as something like 'Henckystrain_136p_1' and 'EngineeringStress_136_1'.

Would this be possible with some sort of loop that operates on files in the folder and continuously saves data columns into variables?

I imagine it would go like:

%For all the files in folder('folder_ex')

%Perform IMPORT FILE COMMAND BELOW

%Save the variables of IMPORTFILE as a concatenation of the file name and 'Stress' or 'Strain';

Any help on functions or documentation would be appreciated. Thanks!

Mike

    function [Henckystrain,EngineeringStress] = importfile(filename, startRow, endRow)
    %IMPORTFILE Import numeric data from a text file as column vectors.
    %   [HENCKYSTRAIN,ENGINEERINGSTRESS] = IMPORTFILE(FILENAME) Reads data from
    %   text file FILENAME for the default selection.
    %
    %   [HENCKYSTRAIN,ENGINEERINGSTRESS] = IMPORTFILE(FILENAME, STARTROW,
    %   ENDROW) Reads data from rows STARTROW through ENDROW of text file
    %   FILENAME.
    %
    % Example:
    %   [Henckystrain,EngineeringStress] = importfile('7Feb14_Alg Only_
    %   136p_1.txt',1, 444);
    %
    %    See also TEXTSCAN.

    % Auto-generated by MATLAB on 2014/02/09 16:48:23

    %%Initialize variables.
    delimiter = '\t';
    if nargin<=2
        startRow = 1;
        endRow = inf;
    end

    %%Read columns of data as strings:
    % For more information, see the TEXTSCAN documentation.
    formatSpec = '%*s%*s%*s%*s%s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%s%[^\n\r]';

    %%Open the text file.
    fileID = fopen(filename,'r');

    %%Read columns of data according to format string.
    % This call is based on the structure of the file used to generate this
    % code. If an error occurs for a different file, try regenerating the code
    % from the Import Tool.
    textscan(fileID, '%[^\n\r]', startRow(1)-1, 'ReturnOnError', false);
    dataArray = textscan(fileID, formatSpec, endRow(1)-startRow(1)+1, 'Delimiter', delimiter, 'ReturnOnError', false);
    for block=2:length(startRow)
        frewind(fileID);
        textscan(fileID, '%[^\n\r]', startRow(block)-1, 'ReturnOnError', false);
        dataArrayBlock = textscan(fileID, formatSpec, endRow(block)-startRow(block)+1, 'Delimiter', delimiter, 'ReturnOnError', false);
        for col=1:length(dataArray)
            dataArray{col} = [dataArray{col};dataArrayBlock{col}];
        end
    end

    %%Close the text file.
    fclose(fileID);

    %%Convert the contents of columns containing numeric strings to numbers.
    % Replace non-numeric strings with NaN.
    raw = repmat({''},length(dataArray{1}),length(dataArray)-1);
    for col=1:length(dataArray)-1
        raw(1:length(dataArray{col}),col) = dataArray{col};
    end
    numericData = NaN(size(dataArray{1},1),size(dataArray,2));

    for col=[1,2]
        % Converts strings in the input cell array to numbers. Replaced non-numeric
        % strings with NaN.
        rawData = dataArray{col};
        for row=1:size(rawData, 1);
            % Create a regular expression to detect and remove non-numeric prefixes and
            % suffixes.
            regexstr = '(?<prefix>.*?)(?<numbers>([-]*(\d+[\,]*)+[\.]{0,1}\d*[eEdD]{0,1}[-+]*\d*[i]{0,1})|([-]*(\d+[\,]*)*[\.]{1,1}\d+[eEdD]{0,1}[-+]*\d*[i]{0,1}))(?<suffix>.*)';
            try
                result = regexp(rawData{row}, regexstr, 'names');
                numbers = result.numbers;

                % Detected commas in non-thousand locations.
                invalidThousandsSeparator = false;
                if any(numbers==',');
                    thousandsRegExp = '^\d+?(\,\d{3})*\.{0,1}\d*$';
                    if isempty(regexp(thousandsRegExp, ',', 'once'));
                        numbers = NaN;
                        invalidThousandsSeparator = true;
                    end
                end
                % Convert numeric strings to numbers.
                if ~invalidThousandsSeparator;
                    numbers = textscan(strrep(numbers, ',', ''), '%f');
                    numericData(row, col) = numbers{1};
                    raw{row, col} = numbers{1};
                end
            catch me
            end
        end
    end

    %%Replace non-numeric cells with NaN
    R = cellfun(@(x) ~isnumeric(x) && ~islogical(x),raw); % Find non-numeric cells
    raw(R) = {NaN}; % Replace non-numeric cells

    %%Allocate imported array to column variable names
    Henckystrain = cell2mat(raw(:, 1));
    EngineeringStress = cell2mat(raw(:, 2));