[GRASSLIST:5690] Unrectified DXF importation

Dear list

Thanks to Sandro for helping me in my first problems
with dxf data.

I have another problems.

I try to import unrectified dxf layer. I manage to do it.
However when I did the transformation using v. transform,
it shows the transformation process with the residual value.
But when I tried to display the rectified dxf. It did not show anything.

I followed the procedure in Neteler and Mitasova’s book but I encounter
a problem such as above.

This is the procedure that I did.

v.in.dxf -a dxf=vmap.dxf prefix=vmap --to import dxf data into ascii

I want to import road layer inside vmap

v.in.ascii in=vmap.road out=vmap_roadxy
v.support vmap_roadxy
g.region -p vect=vmap_roadxy
d.erase
d.vect vmap_roadxy

I managed to display the vmap_roadxy layer on the screen and identify four gcpoints
in x and y coordinates and its location on the map for the real coordinates and
save in in ASCII table point as roadgcp

After that

v.transform in=vmap_road out=vmap_roadtrans point=roadgcp (as in Neteler and Mitasova book)

ERROR:Could not find input vector vmap_road

After that I change the input to the one that I convert to binary file

v.transform in=vmap_roadxy out=vmap_roadtrans point=roadgcp

The map is transformed with the residual value
Transformation is complete

v.support vmap_roadtrans

g.region -p vect=vmap_roadtrans

However, it shows that the region of vmap_roadtrans is similar
to the one that of original or unrectified.

However, I tried

d.vect vmap_roadtrans

but nothing coming out.

Could anyone please help me in this matter.

Thanks in advance

Firuz

On Friday 28 February 2003 08:42 am, Dr. Mohamad Firuz Ramli wrote:

v.transform in=vmap_roadxy out=vmap_roadtrans point=roadgcp

The map is transformed with the residual value
Transformation is complete

v.support vmap_roadtrans

Try v.support -r map=vmap_roadtrans

g.region -p vect=vmap_roadtrans

However, it shows that the region of vmap_roadtrans is similar
to the one that of original or unrectified.

However, I tried

d.vect vmap_roadtrans

but nothing coming out.

Radim

On Fri, Feb 28, 2003 at 03:42:09PM +0800, Dr. Mohamad Firuz Ramli wrote:

Dear list

Thanks to Sandro for helping me in my first problems
with dxf data.

I have another problems.

I try to import unrectified dxf layer. I manage to do it.
However when I did the transformation using v. transform,
it shows the transformation process with the residual value.
But when I tried to display the rectified dxf. It did not show anything.

I followed the procedure in Neteler and Mitasova's book but I encounter
a problem such as above.

This is the procedure that I did.

v.in.dxf -a dxf=vmap.dxf prefix=vmap --to import dxf data into ascii

I want to import road layer inside vmap

v.in.ascii in=vmap.road out=vmap_roadxy
v.support vmap_roadxy
g.region -p vect=vmap_roadxy
d.erase
d.vect vmap_roadxy

I managed to display the vmap_roadxy layer on the screen and identify four gcpoints
in x and y coordinates and its location on the map for the real coordinates and
save in in ASCII table point as roadgcp

Hi,
Up to now the map name is "vmap_roadxy", right?

After that

v.transform in=vmap_road out=vmap_roadtrans point=roadgcp (as in Neteler and Mitasova book)

ERROR:Could not find input vector vmap_road

Yes, because the name was wrong.
v.transform reads binary vectors only:
" v.transform - Transforms an binary vector map layer from one
   coordinate system into another coordinate system."

i.e. the result of v.in.ascii.

After that I change the input to the one that I convert to binary file

v.transform in=vmap_roadxy out=vmap_roadtrans point=roadgcp

Looks better...

The map is transformed with the residual value
Transformation is complete

v.support vmap_roadtrans

Here it may help to use
v.support -r vmap_roadtrans

[should we make "-r" a default?]

g.region -p vect=vmap_roadtrans

Now hopefully shows the correct boundary coordinates.

Markus Neteler