Re: st: dropping matrix columns

[Nick Cox <njcoxstata@gmail.com>]

-svmat- really is an anomaly. I can remember comments about the end of
the last century, and I am being literal and not exaggerating, that it
was due for an overhaul, which never came. But then came Mata and -- I
am imputing a missing statement here -- the implication is that it is
superseded but remains available so as not to break any existing
programs or do-files. It's not worth any developer time to update
something in that condition. It would be like adding an engine to a
donkey.

So, the short and general answer is: Don't write anything now using
-svmat-. There will be a much better way to do what you want using
Mata. In particular, check out -putmata- and -getmata-.

Nick
njcoxstata@gmail.com


On 12 December 2013 16:40,  <altruist81@gmx.de> wrote:
>  Dear Stata Users,
>
> I am using a loop in which many large matrices are created. I want to use (each of) these matrices to create a single new dataset using the -svmat- command. For each of the matrices many of the column names start with a number AND are the columns empty. Since variable names that start with a number are not allowed -svmat- does not work, i.e. I first need to either change get rid of the first numbers in the column names or delete these columns ( I dont need them).
> How can I tell stata to drop all matrix columns for which the name starts with a number OR tell stata to drop all columns in a matrix that are entirely empty?
>
> Many thanks
>
> Darjusch
>
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