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From | "Joseph Coveney" <stajc2@gmail.com> |
To | <statalist@hsphsun2.harvard.edu> |
Subject | Re: st: RE: mata: columns of different eltypes in a transmorphic matrix |
Date | Thu, 10 Oct 2013 21:27:21 +0900 |
Nick Cox wrote: This is an excellent answer, but one simple point seems submerged. An elementary strategy is to put numeric variables in a numeric matrix and string variables in a string matrix. I've often done that in Mata programs, and never yet felt the need for structs, pointers, and so forth. -------------------------------------------------------------------------------- I agree. I'm not sure what László's needs are for keeping Stata dataset string and numeric data in sync in a single location in Mata. Perhaps, if he'd like to elaborate, someone on the list could offer suggestions that don't entail structs or pointer vectors, List or Array classes, and the like. As you could see from my example, taking the long way round involves additional programming steps that in turn give rise to opportunities for logical errors, such as -select(X, missing(X[1,]))- instead of -select(X, !missing(X[1,]))-, and syntax errors, such as -PointerVector = (A, B)- instead of -PointerVector = &A, &B-, among others that I haven't noticed yet. Joseph Coveney * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/faqs/resources/statalist-faq/ * http://www.ats.ucla.edu/stat/stata/