Dear users,
I have a little problem...
I have tried to verify the number of the cells of a dem and of the slope
map derived from it using the r.slope.aspect module...
it seems that the number of cells in the slope map is a little smaller
than in the dem...
is it normal??
I have tried to verify where are the missing cells but I wasn't able to
find them!!!
can you help me???
thanks
ivan
--
Ivan Marchesini
Department of Civil and Environmental Engineering
University of Perugia
Via G. Duranti 93/a
06125
Perugia (Italy)
e-mail: marchesini@unipg.it
ivan.marchesini@gmail.com
tel: +39(0)755853760
fax: +39(0)755853756
hallo,
depending on algoritmus, it could be, that some cells around borders
could be not calculated...
jachym
On Tue, Jul 26, 2005 at 12:03:08PM +0200, ivan marchesini wrote:
Dear users,
I have a little problem...
I have tried to verify the number of the cells of a dem and of the slope
map derived from it using the r.slope.aspect module...
it seems that the number of cells in the slope map is a little smaller
than in the dem...
is it normal??
I have tried to verify where are the missing cells but I wasn't able to
find them!!!
can you help me???
thanks
ivan
--
Ivan Marchesini
Department of Civil and Environmental Engineering
University of Perugia
Via G. Duranti 93/a
06125
Perugia (Italy)
e-mail: marchesini@unipg.it
ivan.marchesini@gmail.com
tel: +39(0)755853760
fax: +39(0)755853756
--
Jachym Cepicky
e-mail: jachym.cepicky@centrum.cz
URL: http://les-ejk.cz
GPG: http://les-ejk.cz/gnupg_public_key/
thanks for your answer Jachym,
do you mean all the cells in the border or only some cells???
I have created two maps having the value=1 using mapcalc:
map1=slope/slope
map2=dem/dem
and later I have tried to subtract the two maps:
map3=map2-map1
the result is a map where all the cells have 0 value (verified with
univar)
this is strange because I would expect that some cells have value=1
how can you explain this behaviour???
any suggestions???
Thank you very much
ivan
Il giorno mar, 26-07-2005 alle 11:57 +0200, Jachym Cepicky ha scritto:
hallo,
depending on algoritmus, it could be, that some cells around borders
could be not calculated...
jachym
On Tue, Jul 26, 2005 at 12:03:08PM +0200, ivan marchesini wrote:
> Dear users,
> I have a little problem...
> I have tried to verify the number of the cells of a dem and of the slope
> map derived from it using the r.slope.aspect module...
> it seems that the number of cells in the slope map is a little smaller
> than in the dem...
> is it normal??
> I have tried to verify where are the missing cells but I wasn't able to
> find them!!!
> can you help me???
> thanks
>
> ivan
>
>
>
> --
> Ivan Marchesini
> Department of Civil and Environmental Engineering
> University of Perugia
> Via G. Duranti 93/a
> 06125
> Perugia (Italy)
> e-mail: marchesini@unipg.it
> ivan.marchesini@gmail.com
> tel: +39(0)755853760
> fax: +39(0)755853756
>
>
>
>
--
Ivan Marchesini
Department of Civil and Environmental Engineering
University of Perugia
Via G. Duranti 93/a
06125
Perugia (Italy)
e-mail: marchesini@unipg.it
ivan.marchesini@gmail.com
tel: +39(0)755853760
fax: +39(0)755853756
I guess that the nuber of cell should be the same in the two raster, maybe the number on non null cell could be different....
have you used r.stats to find out the cell number?
Maxi
ivan marchesini wrote:
thanks for your answer Jachym,
do you mean all the cells in the border or only some cells???
I have created two maps having the value=1 using mapcalc:
map1=slope/slope
map2=dem/dem
and later I have tried to subtract the two maps:
map3=map2-map1
the result is a map where all the cells have 0 value (verified with
univar)
this is strange because I would expect that some cells have value=1
how can you explain this behaviour???
any suggestions???
Thank you very much
ivan
Il giorno mar, 26-07-2005 alle 11:57 +0200, Jachym Cepicky ha scritto:
hallo,
depending on algoritmus, it could be, that some cells around borders
could be not calculated...
jachym
On Tue, Jul 26, 2005 at 12:03:08PM +0200, ivan marchesini wrote:
Dear users,
I have a little problem...
I have tried to verify the number of the cells of a dem and of the slope
map derived from it using the r.slope.aspect module...
it seems that the number of cells in the slope map is a little smaller
than in the dem...
is it normal??
I have tried to verify where are the missing cells but I wasn't able to
find them!!!
can you help me???
thanks
ivan
--
Ivan Marchesini
Department of Civil and Environmental Engineering
University of Perugia
Via G. Duranti 93/a 06125
Perugia (Italy)
e-mail: marchesini@unipg.it
ivan.marchesini@gmail.com
tel: +39(0)755853760
fax: +39(0)755853756
--
-----------------------------------------------------
Massimiliano Cannata
Environmental & Geomatic Engineer
Institute of Earth Scences - SUPSI
Trevano, C.P. 72, CH-6952 Canobbio, SWITZERLAND
Tel: +41 (0)58 / 666 62 18 Fax: +41 (0)58 / 666 62 09
massimiliano.cannata@supsi.ch, www.supsi.ch
-------------------------------------------------------
It was my fault....
sorry to all!!!
all the cells pertaining to the boundary of the investigated area
disappear when I execute r.slope.aspect (due to the way r.slope.aspect
work)
I didn't discover it before because like a dummy I didn't remember of
use the -o option in d.rast...
I apologize with all!!!!!!!
ivan
Il giorno mer, 27-07-2005 alle 16:18 +0200, Massimiliano Cannata ha
scritto:
I guess that the nuber of cell should be the same in the two raster,
maybe the number on non null cell could be different....
have you used r.stats to find out the cell number?
Maxi
ivan marchesini wrote:
>thanks for your answer Jachym,
>do you mean all the cells in the border or only some cells???
>
>I have created two maps having the value=1 using mapcalc:
>
>map1=slope/slope
>map2=dem/dem
>
>and later I have tried to subtract the two maps:
>
>map3=map2-map1
>
>the result is a map where all the cells have 0 value (verified with
>univar)
>this is strange because I would expect that some cells have value=1
>
>how can you explain this behaviour???
>any suggestions???
>
>Thank you very much
>ivan
>
>
>
>
>
>
>
>
>Il giorno mar, 26-07-2005 alle 11:57 +0200, Jachym Cepicky ha scritto:
>
>
>>hallo,
>>depending on algoritmus, it could be, that some cells around borders
>>could be not calculated...
>>
>>jachym
>>
>>
>>On Tue, Jul 26, 2005 at 12:03:08PM +0200, ivan marchesini wrote:
>>
>>
>>>Dear users,
>>>I have a little problem...
>>>I have tried to verify the number of the cells of a dem and of the slope
>>>map derived from it using the r.slope.aspect module...
>>>it seems that the number of cells in the slope map is a little smaller
>>>than in the dem...
>>>is it normal??
>>>I have tried to verify where are the missing cells but I wasn't able to
>>>find them!!!
>>>can you help me???
>>>thanks
>>>
>>>ivan
>>>
>>>
>>>
>>>--
>>>Ivan Marchesini
>>>Department of Civil and Environmental Engineering
>>>University of Perugia
>>>Via G. Duranti 93/a
>>>06125
>>>Perugia (Italy)
>>>e-mail: marchesini@unipg.it
>>> ivan.marchesini@gmail.com
>>>tel: +39(0)755853760
>>>fax: +39(0)755853756
>>>
>>>
>>>
>>>
>>>
>>>
--
Ivan Marchesini
Department of Civil and Environmental Engineering
University of Perugia
Via G. Duranti 93/a
06125
Perugia (Italy)
e-mail: marchesini@unipg.it
ivan.marchesini@gmail.com
tel: +39(0)755853760
fax: +39(0)755853756