bag of words matlab function

cse408_bow.m

% function to create a vocabulary from multiple text files under folders

function feat_vec = cse408_bow(filepath, voc)

[fid, msg] = fopen(filepath, 'rt');
error(msg);
line = fgets(fid); % Get the first line from the file.
feat_vec = zeros(size(voc)); %Initialize the feature vector'

% array of words
W = [];

while line ~= -1
    %PUT YOUR IMPLEMENTATION HERE
    [token, remain] = strtok(line);
    cont = 1;
    while cont
        % lowercase string
        token = lower(token);
        % remove punctuation from word
        token = regexprep(token, '[*/\)(-!,.?]', '');
        % assume there is no more remainder
        cont = 0;
        % store word in word array
        W{end + 1} = char(token);
        % if there is a remainder
        if (~strcmp(remain, ''))
            % get the next word
            [token, remain] = strtok(remain);
            % repeat the loop
            cont = 1;
        end
    end
    % get next line
    line = fgets(fid);
end
% close file
fclose(fid);

% for each item in our vocab
for j=1:length(voc)
    % check each word
    for i=1:length(W)
        % if the word matches an item in the vocab
        if (strcmp(W{i},voc{j}))
            % increment the count for the item
            feat_vec(j) = feat_vec(j) + 1;
        end
    end
end