How would you check diagonally on a wordsearch?

Hello, I am trying to create a function that will find given words in a pre-loaded wordsearch. I have already done checks for words that are left-to-right, right-to-left, top-to-bottom, and bottom-to-top, however I need to do a check for words that are diagonal. I have been trying to come up with my own algorithm for this problem, but it has proven to be quite the adversary. Also, when a word is found, I am to return the row and column of the first letter of the word. I tried using ind2sub but I was getting a value that didn't make any sense. Thank you for any help!

Some information about the wordsearch: It is a 15x15 2 dimensional array filled with characters (letters)

Answer 1

[Walter Roberson]

http://uk.mathworks.com/matlabcentral/answers/257580-create-a-crossword-puzzle#answer_201229

Answer 2

[John D'Errico]

Consider an nxm array, and suppose you wish to generate all diagonal substrings, of length p that go diagonally down to the right. (The other three directions are trivial changes. I'll leave them to the student.)

For example...

n = 5;m = 6;
A = char('a' - 1 + randi(26,[n,m]))
A =
vjnaxx
dziryi
psvjvs
zashsw
plrrjw

p = 3;
[i,j] = ndgrid(1:n-p+1,1:m-p+1);
ind = sub2ind([n,m],i(:),j(:));

A(bsxfun(@plus,ind,[0:(n+1):((p-1)*n+p-1)]))
ans =
vzv
dss
par
jij
zvh
ssr
nrv
ijs
vhj
ays
rvw
jsw

Decide if any of the above rows make a word of length 3. It looks like one of those rows is a word after all. Then repeat for 4 letter words, etc. WTP?

[Shawn Simon]

Is there a way to get what row and column the word is in? Like something similar to getRows in java?

[John D'Errico]

Trivially. Once you figure out that 'par' is a word for example, you will see that it is the 3rd in the list. A test like ismember would suffice for that, assuming you have a list of candidate words to search for.

i(3)
ans =
     3

j(3)
ans =
     1

'par' starts at the (3,1) location in your array, and goes down diagonally to the right.