MATLAB Programming

3 Basic Program Components
Find consecutive matching letters by capturing a letter as a token (.) and
then repeating that letter as a token reference, \1:
idx = regexp(cstr, '(.)\1');
whos idx
Name Size Bytes Class
idx 4x1 296 cell array
idx{:}
ans =
% 'Whose woods these are I think I know.'
8 % |8
ans =
% 'His house is in the village though;'
23 % |23
ans =
% 'He will not see me stopping here'
6 14 23 % |6 |14 |23
ans =
% 'To watch his woods fill up with snow.'
15 22 % |15 |22
To return substrings instead of indices, use the 'match' parameter:
mat = regexp(cstr, '(.)\1', 'match');
mat{3}
ans =
'll' 'ee' 'pp'
Finding Multiple Patterns in Multiple Strings
This example uses a cell array of strings in both the input string and the
expression. The two cell arrays are of different shapes: cstr is 4-by-1 while
expr is 1-by-4. The command is valid as long as they both have the same
number of cells.
Find uppercase or lowercase 'i' followed by a white-space character in
str{1}, thesequence'hou' in str{2}, two consecutive matching letters in
str{3}, and words beginning with 'w' followed by a vowel in str{4}.
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