[GRASS-user] <Q>How to add coordinate (x,y) data?

[SGW00412 at nifty.com]

Hello..!

I want to add coordinate (x, y) data to point-vector-table.
However, I do not know how to do it....

Normally, point-vector-table has not coordinate data.
cat    elev
1     27.000
2     25.000
3     39.000

So, I used addcol command:
v.db.addcol map=xx columns="x single"
v.db.addcol map=xx columns="y single"

cat    elev   x    y
1     27.000 ....  ....
2     25.000 ....  ....
3     39.000 ....  ....

I want to add coordinate data into x, y columns.. for example;

cat    elev       x       y
1     27.000    139.6721 35.14625
2     25.000    139.6230 35.15768
3     39.000    139.6232 35.14543

However, I do not know how to do it....
Please teach me how to add coordinate (x,y) data ?

I want to kriging analysis with R and library(gstat).
I guess, Kiriging (gstat) needs a file including data and coordinate(x,y)data.

Regards,

Yasuo Shimada (Japan)