d=dir('*_p.clv'); % dir struct of all pertinent .csv files
n=length(d); % how many there were
data=cell(1,n); % preallocate a cell array to hold results
for i=1:n
data(i)=csvread(d(i).name); % read each file
end
Now, iff every one of the n .csv files has the same number of rows you can convert to an array...
data=cell2mat(data);
If they aren't all the same length you'll have to augment the shorter to the length of the longest or truncate the longer to that of the shortest.
