[GRASS-user] pb. with netCDF row order

[Eduardo Corbelle Rico]

Hi Nicolas,

it works perfectly now. Thanks a lot again.

Eduardo


O Mar, 26-10-2010 ás 22:39 +0200, Nicolas Pérenne escribiu:
> Hi Eduardo, 
> 
> I have downloaded your file and indeed as you guessed there is a way to
> select the time index, and possibly also a level (altitude or depth)
> index. It goes through optional positional arguments which are not
> documented (sorry), because one has to guess that 'l' stands for the
> time index and 'k' for the level one: 
> 
> bash> nc2grass.sh -h
> Usage: nc2grass.sh [-h]
>        nc2grass.sh [-x <axis name>] [-y <axis name>] [-z <axis name>]
>                    [-t <axis name>] [-m <missing value>]
>                    <netCDF file> <variable> <imin> <imax> <jmin> <jmax>
> [<l> [<k>]]
>   -h: help
>   -x: axis name in input file. Default: longitude
>   -y: axis name in input file. Default: latitude
>   -z: axis name in input file. Default: z
>   -t: axis name in input file. Default: time
>   -m: missing value code in output header. Default: -9.99e+02
> 
> Actually in your case 'ncdump -h' shows that the missing value flag is
> 1.e+30f and you can tell GRASS about it using the -m option; my
> experience is that you have to provide this flag with the very same
> formatting given to awk in the script, that is "+1.00e+30" (check out
> the default value). 
> 
> To get the first time index in your file: 
> nc2grass.sh -m +1.00e+30 t2m.mean.KNMI.HA2.nc t2m 1 100 1 80 1 > \
> t2m_l1.txt
> latN latS lonE lonW:
> 74.7500000 35.2500000 34.7500000 -14.7500000
> 
> Or you can automate the extraction like this: 
> 
> bash> for l in 1 2 3 4; do
> >nc2grass.sh -m +1.00e+30 t2m.mean.KNMI.HA2.nc t2m 1 100 1 80 $l > \
> t2m_l$l.txt
> >done
> latN latS lonE lonW:
> 74.7500000 35.2500000 34.7500000 -14.7500000
> latN latS lonE lonW:
> 74.7500000 35.2500000 34.7500000 -14.7500000
> latN latS lonE lonW:
> 74.7500000 35.2500000 34.7500000 -14.7500000
> latN latS lonE lonW:
> 74.7500000 35.2500000 34.7500000 -14.7500000
> bash> ls
> t2m_l1.txt  t2m_l2.txt  t2m_l3.txt  t2m_l4.txt  t2m.mean.KNMI.HA2.nc 
> 
> One potential shortcoming of the script though is that you may provide a
> time index, or a time index and a level index, but not a level index
> alone... a fix could be to provide 'k' and 'l' as options instead of
> positional arguments. 
> 
> Hope it helps. 
> 
> 
> Le mardi 26 octobre 2010 à 12:48 +0200, Eduardo Corbelle Rico a écrit : 
> > Nicolas,
> > 
> > I've been struggling with the issue of row order in netCDF files and
> > your post came perfect for me. Thank you very much for it.
> > 
> > I still have a problem that surely you or anyone in the list would find
> > trivial: the file I'm trying to convert 
> > 
> > (downloadable in the Prudence project:
> > http://prudence.dmi.dk/data/seasonal/KNMI/t2m.mean.KNMI.HA2.nc.gz )
> > 
> > has four time bands, which I can't write separately into different ascii
> > files.
> > 
> > I'm using the script as...
> > 
> > ./nc2grass-0001.bin t2m.mean.KNMI.HA2.nc t2m 1 100 1 80 > t2m.txt
> > 
> > ...and the four time (seasonal) bands came together in the same ascii
> > line.
> > 
> > Should I use any additional argument with the script to be able to get
> > four separate ascii files?
> > 
> > Thanks a lot!
> > 
> > 
> 
> 
> 
>