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Switch Case where case is a word_anynumber

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I am trying to make a switch case where the case is satisfied by the following:
word_anynumber (ie word_1 or word_2 etc)
what do i do to achieve this?
The issue is that i want the case to do the same thing for any case with word_#, but i don't want to create cases for each number because i have a variable number of numbers each time this script runs.
Any help would be greatly appreciated.

Accepted Answer

Daniel Shub
Daniel Shub on 15 Nov 2011
A regular expression might be useful for this type of task. Using the following as the test case:
a = cellstr([repmat('word_', 100, 1), num2str((0:99)', '%02d')]);
b = cellstr([repmat('Word_', 100, 1), num2str((0:99)', '%02d')]);
c = cellstr([repmat('xword_', 100, 1), num2str((0:99)', '%02d')]);
x = [a;b;c];
The following:
~cellfun(@isempty, regexp(x, 'word_[0-99]', 'matchcase'));
will return true for any x that is word_# and fail on case changes. How to build your case/switch around this is not clear (it seems like an if/elseif/else problem to me.
  1 Comment
Jonathan Crider
Jonathan Crider on 15 Nov 2011
Thank you for your help. I ended up switching from a switch case to a if/elseif and used the regexp(x, 'word_[0-99]', 'matchcase') expression and it is working. This will be good for now, but i may revisit this later for speed reasons. Thank you all for your help.

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More Answers (2)

Fangjun Jiang
Fangjun Jiang on 14 Nov 2011
Use strfind(), strcmp() or strmatch(). You may also consider use "if-else" rather than 'case-switch"
if strfind(StrVariable,'word_')
  1 Comment
Daniel Shub
Daniel Shub on 15 Nov 2011
I think this will evaluate to true if StrVariable is of the form * word_*. It doesn't require word to be the first element, numbers to follow the underscore, or the numbers to be the final elements.

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Jonathan on 14 Nov 2011
If all of your cases are similar to what you describe, then you can use strtok like this.
a = 'word_4';
b = 'word_27';
c = 'byte_3';
d = 'bit_14';
switchStr = a;
switch strtok(switchStr, '_')
case 'word'
case 'byte'
case 'bit'
This displays 'word'. Try repeating this with switchStr set to b, c, and d.
Jonathan on 15 Nov 2011
strtok does work in this case since "strtok('apple', '_')" returns the string "apple".
Jonathan on 15 Nov 2011
a = 'apple';
b = 'orange';
c = 'banana';
d = 'grape_1';
e = 'grape_2';
f = 'grape_3';
switchStr = d; % goes through a through f
switch strtok(switchStr, '_')
case 'apple'
case 'orange'
case 'banana'
case 'grape' % this is where i have a problem

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