To Richard's excellent explanation I will add a
few comments:
Even Stata user-programmers tend to start writing
programs using a new version's features pretty soon as it
is released. Sometimes that's essential for what
they want to do; sometimes it is just more congenial
to use improved language features. We are now some way
into the lifetime of Stata 8 and it's a sad fact that
those still on previous versions are increasingly
left behind in terms of being able to use the
full range of Stata add-ons.
In the case of -mvis- a quick glance suggests
that you might be able to hack it to -version 7-
and it would remain legal and correct. But that
would gain you nothing, really. -mvis- is just part
of a package and the whole package would need
to be scanned in a bid to remove Stata 8 features,
which would I guess require considerable programming
expertise. Someone would need to able to recognise
Stata 8 features and translate them into a Stata 7
equivalent; people with this knowledge tend to
be using Stata 8 already.
Nick
[email protected]
Richard Williams replied to Dave Purcell
> >A few questions:
> >
> >1) I just installed Patrick Royston's mvis ado (and related
> files) and
> >tried to run it, but I'm getting a "version 8 not supported"
> error. Is
> >it safe to assume I can't use this with the version 7 I'm
> running (Born 08 Aug 2001)?
> >
> >3) Is there a way to tell if an ado file requires a certain version?
> >I've looked through the FAQs and haven't come across an answer.
> Stata recommends that you specify the version of Stata you
> are using at the
> top of programs and do-files that you write. Hence,
> somewhere early on in
> an ado file you'll see a line like
>
> version 8.2
>
> Try to run that program in an earlier version of Stata and you'll get
> errors like you saw.
>
> Now, it is always possible that the program would work fine
> with an earlier
> version of Stata. So, you could try making a copy, changing
> the version to
> 7, and see what happens. But, keep in mind that (a) it may
> not work at
> all, because it requires version 8 features, and (b) worse
> still, it may
> seem to work but give the wrong answers. The author will
> typically only
> have tested it with the version of Stata they happen to have,
> so there are
> no guarantees if you try it with a lower level version.
>
> So, I suppose you could try to hack the programs; but if you did, I'd
> suggest making sure you run them on problems with known
> results to see if
> it seemed to be working correctly. I don't know anything
> about -mvis- but
> I see that it deals with missing data, so one immediate
> concern I would
> have is whether it is dependent on the changes in MD that
> were made in version 8.
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
