[daip] Maximum number of flags

[Eric Greisen]

Enno Middelberg wrote:
> Hi,
> 
> 
> I'm using a custom script to flag GMRT data in Aips, which produces very 
> granular flagging information, and so my FG tables have 100000 and more 
> rows. When I try to apply the flags to the data using UCVOP, it aborts with
> 
> UVCOP2: TOO MANY FLAGS AT SAME TIME (>****)
> UVCOP2: COPYUV: COPYIT ERROR 10
> 
> 
> In particular, I have 294129 rows in this FG table.
> 
> Browsing the source code I find a parameter MAXFLG in UVCOP.FOR, which 
> is set to 60001. I have two questions related to that:
> 
> 1 - is this parameter significant, or can MAXFLG be increased to, say, 
> 600000 or more without consequences?
> 
> 2 - how come that flagging tables with ~100000 rows, which I have dealt 
> with before, are possible and don't cause UVCOP to abort?

As the message says, it is a question of the  number of flags applying 
to a single time (so long as the data are in time order).  That you have 
 > 60000 flags applying to a single time is a tad worrisome since it is 
 >= 20% of all of your flags.  To raise the number in UVCOP costs 60 
bytes per allowed number or ~30 Mbytes to go to 600000.  I suspect that 
simply double the limit (and fixing the format) will probably resolve 
your problem.

Eric Greisen