MATLAB Programming

3 Basic Program Components
As a simple example, if you wanted to search for identical sequential letters
in a string, you could capture the first letter as a token and then search for
a matching character immediately afterwards. In the expression shown
below, the (\S) phrase creates a token whenever regexp matches any
non-whitespace character in the string. The second part of the expression,
'\1', looks for a second instance of the same character immediately following
the first:
poestr = ['While I nodded, nearly napping, ' ...
'suddenly there came a tapping,'];
[mat tok ext] = regexp(poestr, '(\S)\1', 'match', ...
'tokens', 'tokenExtents');
mat
mat =
'dd' 'pp' 'dd' 'pp'
The tokens returned in cell array tok are:
'd', 'p', 'd', 'p'
Starting and ending indices for each token in the input string poestr are:
11 11, 26 26, 35 35, 57 57
UsingTokens—Example1
Here is an example of how tokens are assigned values. Suppose that you
are going to search the following text:
andy ted bob jim andrew andy ted mark
You choose to search the above text with the following search pattern:
and(y|rew)|(t)e(d)
This pattern has three parenthetical expressions that generate tokens. When
you finally perform the search, the following tokens are generated for each
match.
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