[GRASS-user] representing missing values (attributes) in vector/site point data

Dear GRASS users,

I am using v.vol.rst module for spatial interpolation of monthly rainfall
values obtained from rain-gauge stations.
I am using module v.in.sites (or v.in.ascii) module to create the vector point
map of station station rainfall.

We don't have values for rainfall at all stations all the time. I want to
know how can I represent missing values of rainfall (attributes) in a vector
map so that these points are left in interpolation.
(One way to do that is leave that point altogether from vector map, but I
don't want do that as i am interested in looking CV errors at each of the
stations)

Thanks in advance,

With regards,
Suprit

--
Suprit kumar
Research Fellow
Physical Oceanography Division
National Institute of Oceanography
Dona Paula 403 004 Goa, India.

Email:supritATnio.org/suprit.kumarATgmail.com

Tel : +91-(0)832-2450-400