I'm assuming each cell in inventors is a cell array of strings. It wouldn't make sense for these to be actual floating point or intenger numbers, because the dash would subtract the two numbers separating them together. Now, because you're writing to a CSV file, the easiest thing I can think of is to iterate over each number and cell, then repeat the ID number for as many times as there are elements in a cell. First create the right headers, then write your results. Something like this comes to mind:
f = fopen('data.csv', 'w'); %// Open up data for writing
fprintf(f, 'pnum,inventors\n'); %// Write headers
for ii = 1 : numel(pnum) %// For each unique number
inventor = inventors{ii};
for jj = 1 : numel(inventor) %// For each inventor ID
fprintf(f, '%d,%s\n', pnum(ii), inventor{jj}); %// Write the right combo to file
end
end
fclose(f); %// Close the file
fopen here opens up a file called data.csv so we can write things to it. What is returned is a file pointer called f, which we use to write stuff to this file. After, we write the headers of the file, consisting of pnum and inventors. This is a CSV file so there's a comma separating the two. Now, for each unique number, we then access the right slot in inventors then for each unique inventor, add the same unique ID with the right inventor ID as a line in this file. I use fprintf to write things to file using the associated file pointer established earlier. Once we're done, close the file with fclose.
To double check that this works, I've used the small example you've provided in your post:
pnum = [5384940 5437561 5570271 5661637 5771155];
inventors = {{'5012491-01', '2035147-03'}.', {'5437561-01', '5437561-02', '5437561-03', '5012491-02'}.', {'5437561-03'}, {'1885634-08'}, {'5012491-01'}};
Bear in mind that I don't have access to your struct, so you'll have to access the right fields and assign them to the corresponding variables seen above. So if your struct is called something like data, then you'd do this before you run the above code:
pnum = data.pnum;
inventors = data.inventors;
Running the above code I just wrote and opening up the CSV file (which is called data.csv), I get this:
pnum,inventors
5384940,5012491-01
5384940,2035147-03
5437561,5437561-01
5437561,5437561-02
5437561,5437561-03
5437561,5012491-02
5570271,5437561-03
5661637,1885634-08
5771155,5012491-01
