[GRASSLIST:832] Re: UNSOLVABLE problem in GRASS!!?

Mon Jul 28 02:58:52 EDT 2003

I think your desired result shold be a raster map with slope value
only inside the watershed.
Is it right?
If it is, once you have your raster boundary map (suppose with
value=1 inside and value=0 outside) and your raster slope map you
should run r.mapcalc so to have NULL outside and slope inside.
(something like this but check the rigth formalism:
if
boudary = 0 final_map=NULL
else if
boundary=1 final_map=slope_map)

Ramin Safa wrote:

> Hi,Massimiliano
> Hi,All
> Regarding your reply:
> for items 1 and 2 ok.,but for item3:
> we can not mask for raster map slope another map,we can
> only creat a raster map that work with special slope(for
> example slope Less than 60%),but we can not creat it,as a
> work inside of watershed or outside of watershed because
> the watershed boundry is in diffrent map.
> any way,i,ve done these:
>
> 1.reclass slope map(to simpliphy)...
> 2.raster to vector by r.poly
> 3.v.patch watershed boundry ,slope map
> until here every thing is ok,and i have area for slope
> clases but in the squer.. but NOT ..in the watershed map(by
> r.report)
> 4.v.cutter for omitting out of watershed area(vector map is
> ok)but:
> 5.v.report or d.what vect....there is no any data in area
>
> So,I thought about this problem and did anything should be
> do,this problem is related to software or program,it can
> not do this.
> If somebody knows ,please tell me.
> Regard
> Ramin
>
> 4.
> --- Massimiliano Cannata
> <massimiliano.cannata at ist.supsi.ch> wrote:
> > I'm not sure to have understand all, but:
> >
> > 1- a raster map is a "box" rappresentation, in fact in a
> > raster
> > ascii you have an header that says the coordinate
> > extention of your
> > "box" (or better to say region). So you cannot have any
> > border on
> > it.
> >
> > 2- when you intepolate you will always have some border
> > problem,
> > that's because on your border (note, the border of your
> > interpolated set of line or point) you have only one side
> > value,
> > while on the other you have null value so you begin to
> > invent....
> > it's usually done to keep a larger area and then take off
> > a buffer.
> >
> > 3- if you want to have a raster with your value only
> > inside the
> > watershed consider to interpolate, calculate slope and
> > after assign
> > a null value outside you interest region. I f you can
> > create a
> > raster that works as a mask (for example with value=1
> > inside your
> > watershed and value=0 outside) you can easly do it with
> > r.mapcalc.
> >
> >
> > Ramin Safa wrote:
> >
> > > Hi
> > > Regarding folowing email
> > > My area is a watershed but:
> > > I don want to do r.watershed
> > > I need to use only my area(watershed ) not a
> > squer(whole
> > > screen)and i need slope,,...
> > > please if anybody knows ,help me
> > > sincerely
> > > Ramin
> > >
> > > Note: forwarded message attached.
> > >
> > > =====
> > >
> > > Ramin Safamanesh
> > > Department of  Environment Science , UPM
> > > Email :  rsafamanesh at hotmail.com Tel  :  0060122399448
> > >
> > > __________________________________
> > > Do you Yahoo!?
> > > Yahoo! SiteBuilder - Free, easy-to-use web site design
> > software
> > > http://sitebuilder.yahoo.com
> > >
> > >   --------------------------------------------------
> > >
> > > Subject: [GRASSLIST:781] slope map
> > > Date: Mon, 21 Jul 2003 18:53:15 -0700 (PDT)
> > > From: Ramin Safa <raminsafa at yahoo.com>
> > > To: mlennert at club.worldonline.be, grasslist at baylor.edu
> > >
> > > hi
> > > *Regarding slope map(raster),befor v.to.rast my map had
> > a
> > >   border but after v.to.rast  ..the border is
> > disapeared
> > > and **because of this when i run : r.slop.aspect
> > ....slope
> > > map
> > >    and aspect map and .. will be wrong, am i right or
> > no?
> > > ***if this is true how i save the border and if it is
> > not
> > >
> > >    true how i solve my problem?
> > > ****and also if i run v.surf.rst or r.surf contour i
> > have
> > >    same problem :out of the borderplace(but dont have
> > >    border) the colors is confused.
> > > actually i think ,in vector map the border is a
> > continuse
> > >    of end of contours line(related to digitizing)..
> > > Regards
> > > Ramin
> > > ---
> > >  Moritz Lennert <mlennert at club.worldonline.be> wrote:
> > > > Ramin Safa said:
> > > > > hi Moritz
> > > > > thanks ,i did v.transfom.
> > > >
> > > > And did it work correctly ? Have you checked with
> > > > d.what.vect to see the
> > > > resulting attribute values ?
> > > >
> > > > > but now please go to problem
> > > > no:737<grasslist>r.slop.aspect
> > > >
> > > > I've seen your mail, but can't answer your question
> > > > without more
> > > > information about your data. On what file did you run
> > > > r.slope.aspect ?
> > > >
> > > > > the answers is not real and not correct.
> > > >
> > > > Then probably the data is not correct.
> > > >
> > > > > r. report also is no correct.
> > > >
> > > > idem
> > > >
> > > > > i dont know why.
> > > >
> > > > One reason might be that your contours were actually
> > > > digitized as areas,
> > > > not as lines. You might want to try by transforming
> > all
> > > > the areas to lines
> > > > (you could use v.area2line). After the transformation
> > you
> > > > would have to go
> > > > into v.digit and lable the lines, but seen that you
> > don't
> > > > have too many of
> > > > them, this shouldn't be too much work. Then you could
> > use
> > > > v.surf.rst or
> > > > something like that.
> > > >
> > > > Moritz
> > >
> > > __________________________________
> > > Do you Yahoo!?
> > > Yahoo! SiteBuilder - Free, easy-to-use web site design
> > software
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> >
> > --
> > -------------
> > Ing.  Massimiliano Cannata
> > Istituto di Scienze della Terra - SUPSI
> > C.P. 72 - CH-6952 Canobbio (Ticino, Switzerland)
> > Tel +41 91 /935 12 25 - Fax +41 91 /935 12 09
> > eMail: massimiliano.cannata at ist.supsi.ch
> > Internet: http://www.ist.supsi.ch
> >
>
> __________________________________
> Do you Yahoo!?
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> http://sitebuilder.yahoo.com

--
-------------
Ing.  Massimiliano Cannata
Istituto di Scienze della Terra - SUPSI
C.P. 72 - CH-6952 Canobbio (Ticino, Switzerland)
Tel +41 91 /935 12 25 - Fax +41 91 /935 12 09
eMail: massimiliano.cannata at ist.supsi.ch
Internet: http://www.ist.supsi.ch