David,
Ah, "namelist" looks very useful. I was looking at version 7
manual which does not appear to have this useful feature. Will pursue...
On Tue, 19 Jul 2005, David Kantor wrote:
> At 06:36 PM 7/19/2005 -0400, Herb Smitt wrote:
> >This is a programming question.
> >
> >I have a program, "project" that takes two matrixes (say, "matrix1" and
> >"matrix2") and a number (say, "n") and returns a result as a matrix (say,
> >"matrix0"). I have no trouble writing a program that calls the routine
> >via
> >
> >. project matrix0 matrix1 matrix2 n
> >
> >along the lines
> >
> >. program project
> >. args result history ratios years
> >
> >where "result" etc. are local macros corresponding to the arguments being
> >passed in the call or command line.
> >
> >My problem is: What happens if sometimes when I want to run the routine,
> >I want to pass another argument, say, "matrix3", but sometimes I do not?
> >If I make this argument the last in the local macros, e.g.,
> >
> >. program project
> >. args result history ratios years births
> >
> >how can I see whether "matrix3" was passed to `births' or not? I.e.,
> >
> >. project matrix0 matrix1 matrix2 n matrix3
> >
> >versus
> >
> >. project matrix0 matrix1 matrix2 n ?
> >
> >Similarly, how can I allow "n" not to be specified in the call line?
> >
> > All of this is simple with "syntax" instead of "args", except I do
> >not understand how to pass (call) matrixes using syntax...
> >
> > Thanks in advance for any help....
> >
> > --Herb Smith
> >
> >Professor of Sociology and
> >Director, Population Studies Center
> >3718 Locust Walk CR
> >University of Pennsylvania
> >Philadelphia, PA 19104-6298
> >
> >[email protected]
> >
> >215.898.7768 (office)
> >215.898.2124 (fax)
>
> I believe you can use the -namelist- feature of -syntax-.
>
> Another possibility (if namelist doesn't prove useful) is as a set of options:
> syntax ... , mat1(string) mat1(string) [mat3(string) ]
>
> HTH
> --David
>
> David Kantor
> Institute for Policy Studies
> Johns Hopkins University
> [email protected]
> 410-516-5404
>
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