Comments on: A Way to Automate “Regular” Renaming http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/ Loren Shure works on design of the MATLAB language at MathWorks. She writes here about once a week on MATLAB programming and related topics. Wed, 15 Feb 2012 15:23:22 +0000 hourly 1 http://wordpress.org/?v=3.2.1 By: Loren http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-29709 Loren Wed, 20 Aug 2008 10:17:51 +0000 http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-29709 Vijay- I would loop through the replacement strings myself. Not sure if there's a regexp way to do it. --Loren Vijay-

I would loop through the replacement strings myself. Not sure if there’s a regexp way to do it.

–Loren

]]> By: Vijay http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-29706 Vijay Tue, 19 Aug 2008 21:34:21 +0000 http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-29706 Loren - Assume i want to replace ocurrences of 'Monday', 'Tuesday', 'Wednesday', in a string with 'mon', 'tue', 'wed' respectively. Can this be done with one or two lines of code? I am currently using case statements. Loren – Assume i want to replace ocurrences of ‘Monday’, ‘Tuesday’, ‘Wednesday’, in a string with ‘mon’, ‘tue’, ‘wed’ respectively. Can this be done with one or two lines of code? I am currently using case statements.

]]> By: Gordon Saksena http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-28355 Gordon Saksena Fri, 18 Apr 2008 15:13:47 +0000 http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-28355 Though I had fiddled with regular expressions before, they really clicked after reading the first part of "Mastering Regular Expressions" by Jeffrey Friedl. He explains what regular expression engines do internally, which helped me organize the myriad of special regexp symbols and gave me an intuition into what is possible. Though I had fiddled with regular expressions before, they really clicked after reading the first part of “Mastering Regular Expressions” by Jeffrey Friedl. He explains what regular expression engines do internally, which helped me organize the myriad of special regexp symbols and gave me an intuition into what is possible.

]]> By: Francois http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-28075 Francois Mon, 31 Mar 2008 13:04:09 +0000 http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-28075 I agree, regular expression should be part of the training for programmers or any relevant disciplines. I agree, regular expression should be part of the training for programmers or any relevant disciplines.

]]> By: Loren http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-27891 Loren Fri, 28 Mar 2008 21:37:53 +0000 http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-27891 Scott- Indeed yes, train with examples. That's the holy grail. --Loren Scott-

Indeed yes, train with examples. That’s the holy grail.

–Loren

]]> By: Loren http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-27890 Loren Fri, 28 Mar 2008 21:12:41 +0000 http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-27890 Scott- In <a href="http://www.mathworks.com/access/helpdesk/help/techdoc/matlab_prog/f0-39483.html" rel="nofollow">this part of the doc</a> under "Using Arrays as Indices", you will see you can loop over the columns of any kind of array, not just a row vector of numbers. MATLAB has behaved like that from the inception. --Loren Scott-

In this part of the doc under “Using Arrays as Indices”, you will see you can loop over the columns of any kind of array, not just a row vector of numbers. MATLAB has behaved like that from the inception.

–Loren

]]> By: Scott Miller http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-27889 Scott Miller Fri, 28 Mar 2008 21:09:28 +0000 http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-27889 Loren, Having now tried the latest version of regExpHelper, I find that it is better than the initial release. There is enough in the comment lines to sort out how to use it, and I was able to get a part of your regexp code to run: '_+(\w?)'. That alone is potentially a great help. A *usable* tool is certainly available in the form of regExpHelper. Now if only it could learn from examples... Scott Loren,

Having now tried the latest version of regExpHelper, I find that it is better than the initial release. There is enough in the comment lines to sort out how to use it, and I was able to get a part of your regexp code to run:
‘_+(\w?)’. That alone is potentially a great help.

A *usable* tool is certainly available in the form of regExpHelper. Now if only it could learn from examples…

Scott

]]> By: Scott Miller http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-27888 Scott Miller Fri, 28 Mar 2008 20:56:50 +0000 http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-27888 Loren, A nice little piece. Once again, I find I learn the most about programming by reading OPC (Other People's Code!). In this case, 'type' doesn't appear as a keyword when I do a search, but it works. Confronted with this problem, I would think "regexp", then struggle with the rules for a while until I got a solution, perhaps consulting with a C/C++ colleague down the hall, and perhaps looking at some other code in FEX. It is a shame that there isn't a usable tool to help with this problem - see my comments on http://www.mathworks.com/matlabcentral/fileexchange/loadFile.do?objectId=15215&objectType=file which appears to be a foray in the right direction. The ability to loop 'for' over a list, as in 'for name = names' isn't described in the TMW documentation either. Since the latter structure appears in some languages, I had previously tried this construction, but found that it works for some instances and not others. Having said that, I have just tried to get it to fail, and can't do it. Since the documentation doesn't describe this usage, could you go over the allowed syntax? Scott Loren,

A nice little piece. Once again, I find I learn the most about programming by reading OPC (Other People’s Code!). In this case, ‘type’ doesn’t appear as a keyword when I do a search, but it works.

Confronted with this problem, I would think “regexp”, then struggle with the rules for a while until I got a solution, perhaps consulting with a C/C++ colleague down the hall, and perhaps looking at some other code in FEX. It is a shame that there isn’t a usable tool to help with this problem – see my comments on

http://www.mathworks.com/matlabcentral/fileexchange/loadFile.do?objectId=15215&objectType=file

which appears to be a foray in the right direction.

The ability to loop ‘for’ over a list, as in ‘for name = names’ isn’t described in the TMW documentation either. Since the latter structure appears in some languages, I had previously tried this construction, but found that it works for some instances and not others. Having said that, I have just tried to get it to fail, and can’t do it. Since the documentation doesn’t describe this usage, could you go over the allowed syntax?

Scott

]]> By: Antunes http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-27885 Antunes Fri, 28 Mar 2008 18:15:39 +0000 http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-27885 Regular expressions are great -this was the reason why I learned PERL. I use Matlab most of the time and would prefer to use regexps without leaving my favorite tool. However, I am not aware of any book discussing regexps in Matlab. So here's a request: a Matlab book on string parsing with regexps oriented to scientific problems (bioinformatics, text mining, etc.). This is much needed. Antunes Regular expressions are great -this was the reason why I learned PERL. I use Matlab most of the time and would prefer to use regexps without leaving my favorite tool. However, I am not aware of any book discussing regexps in Matlab.

So here’s a request: a Matlab book on string parsing with regexps oriented to scientific problems (bioinformatics, text mining, etc.). This is much needed.

Antunes

]]> By: Graeme E. Smith http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-27882 Graeme E. Smith Fri, 28 Mar 2008 16:37:01 +0000 http://blogs.mathworks.com/loren/2008/03/27/a-way-to-automate-regular-renaming/#comment-27882 I think the regular expression is one of those: if-you-know-how-to-use-it-more-power-to-you type features. I had a little experience using them some years ago: on the one hand, when they worked they were incredible; but on the other hand when they didn't work I found them a nightmare to debug. I think it's well worth remember that they're available in Matlab, but like many features of computing, unless you have cause to use them on a regular basis it's unlikely you'll become a master. I think the regular expression is one of those: if-you-know-how-to-use-it-more-power-to-you type features. I had a little experience using them some years ago: on the one hand, when they worked they were incredible; but on the other hand when they didn’t work I found them a nightmare to debug. I think it’s well worth remember that they’re available in Matlab, but like many features of computing, unless you have cause to use them on a regular basis it’s unlikely you’ll become a master.

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