[GRASS-user] Problems with v.to.db and v.db.addcol

Under my Windows GRASS GIS the commands v.to.db and v.db.addcol did not work properly, when I wanted to calculate the areas of polygons. There were error meaaages that it could not poen or execute the dbase files. Does anybody how to overcome this problem ?

Best regards

Niels

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-----------------------------------------------------
Dr. Niels Thevs
Chair of Geobotany and Landscape Ecology
Institute of Botany and Landscape Ecology
Greifswald University
Grimmer Strasse 88
17487 Greifswald
Germany

Tel.: +49-3834-86-4137
Fax: +49-3834-86-4114

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Could you please post the precise error message?

Thanks
Markus

On Jan 29, 2008 8:54 PM, Niels Thevs <nt001582@uni-greifswald.de> wrote:

Under my Windows GRASS GIS the commands v.to.db and v.db.addcol did not
work properly, when I wanted to calculate the areas of polygons. There
were error meaaages that it could not poen or execute the dbase files.
Does anybody how to overcome this problem ?

Best regards

Niels

--

-----------------------------------------------------
Dr. Niels Thevs
Chair of Geobotany and Landscape Ecology
Institute of Botany and Landscape Ecology
Greifswald University
Grimmer Strasse 88
17487 Greifswald
Germany

Tel.: +49-3834-86-4137
Fax: +49-3834-86-4114

-----------------------------------------------------

--
Markus Neteler
Fondazione Mach - Centre for Alpine Ecology
38100 Viote del Monte Bondone (Trento), Italy
neteler AT cealp.it http://www.cealp.it/

I tried the v.to.db (Windows-Grass) again. Today no error message came out. But, with the default settings these messages came out:

v.to.db map=training_area_2_x_unsupervised_class_50@PERMANENT type=point,line,boundary,centroid layer=1 qlayer=1 option=area units=hectares column=b_label

Updating database...

5104 categories read from map

5104 records selected from table

5104 categories read from map exist in selection from table

0 categories read from map don't exist in selection from table

5104 records updated/inserted

0 update/insert errors

Then, I changed type to area:

v.to.db map=training_area_2_x_unsupervised_class_50@PERMANENT type=area layer=1 qlayer=1 option=area units=hectares column=b_label

ERROR: value <area> out of range for parameter <type>
        Legal range: point,line,boundary,centroid

Best regards

Niels

Markus Neteler schrieb:

Could you please post the precise error message?

Thanks
Markus

On Jan 29, 2008 8:54 PM, Niels Thevs <nt001582@uni-greifswald.de> wrote:

Under my Windows GRASS GIS the commands v.to.db and v.db.addcol did not
work properly, when I wanted to calculate the areas of polygons. There
were error meaaages that it could not poen or execute the dbase files.
Does anybody how to overcome this problem ?

Best regards

Niels

--

-----------------------------------------------------
Dr. Niels Thevs
Chair of Geobotany and Landscape Ecology
Institute of Botany and Landscape Ecology
Greifswald University
Grimmer Strasse 88
17487 Greifswald
Germany

Tel.: +49-3834-86-4137
Fax: +49-3834-86-4114

-----------------------------------------------------

--

-----------------------------------------------------
Dr. Niels Thevs
Chair of Geobotany and Landscape Ecology
Institute of Botany and Landscape Ecology
Greifswald University
Grimmer Strasse 88
17487 Greifswald
Germany

Tel.: +49-3834-86-4137
Fax: +49-3834-86-4114

-----------------------------------------------------

On Jan 30, 2008 9:01 AM, Niels Thevs <nt001582@uni-greifswald.de> wrote:
...

Then, I changed type to area:

v.to.db map=training_area_2_x_unsupervised_class_50@PERMANENT type=area
layer=1 qlayer=1 option=area units=hectares column=b_label

ERROR: value <area> out of range for parameter <type>
        Legal range: point,line,boundary,centroid

Yes, because "area" isn't supported (use boundary instead).

Best regards
Markus