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<== Date ==> <== Thread ==>

Subject: Re: Setting an array to zero length
From: Ben Franksen via Tech-talk <tech-talk at aps.anl.gov>
To: "Rogers, Will (DLSLtd,RAL,LSCI)" <will.rogers at diamond.ac.uk>, "tech-talk at aps.anl.gov" <tech-talk at aps.anl.gov>
Date: Fri, 3 Apr 2020 15:04:08 +0200
Am 03.04.20 um 12:43 schrieb Rogers, Will (DLSLtd, RAL, LSCI) via Tech-talk:
> I suspect that this may not be a simple question, but:
> 
> *   If I create a waveform WAVE with a soft IOC of length 10, it has
> WAVE.NELM as 10 and WAVE.NORD as 0 *   If I caput 5 elements to it
> (e.g. with Cothread) it has WAVE.NELM as 10 and WAVE.NORD as 5
> 
> Is there a way to restore it to its uninitialised state with
> WAVE.NORD as 0? How general could this be for different record
> types?

The first thing I would try is:

  caput -a WAVE 0

If this doesn't work, it could be that 'caput' is broken. The next thing
to try is to do this from Python. You could also try to use another
record with NELM=NORD=0 and that has an output link that you point to
your WAVE record. There is no record type in base with such an output
link but perhaps other modules have one.

If that doesn't work either, you should issue a bug report because this
is something that should be possible.

Cheers
Ben
-- 
...it is impossible to speak of a depoliticized economy as the liberals
do, or of a separation between economic exploitation and political
oppression as the Marxists articulate. The basic distinction, rather, is
between power and creativity...
             -- Jonathan Nitzan and Shimshon Bichler: Capital as Power

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Replies:
Re: Setting an array to zero length Ben Franksen via Tech-talk
Re: Setting an array to zero length Ralph Lange via Tech-talk
References:
Setting an array to zero length Rogers, Will (DLSLtd, RAL, LSCI) via Tech-talk

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