[GRASS-user] Creating a ground water from a vector files of contours?

Fri Feb 23 13:14:06 EST 2007

Hi Dylan,

I know how to import the contours and I know how to import the centroids.   But I do not know how to merge the two.  Can you show me the steps I have to take up to the merge step?

Thanks for your help!

Bob

-----Original Message-----
From: Dylan Beaudette [mailto:dylan.beaudette at gmail.com]
Sent: Thursday, February 22, 2007 1:02 PM
To: Moskovitz, Bob; grassuser at grass.itc.it
Subject: Re: [GRASS-user] Creating a ground water from a vector files of
contours?

Hi bob,

hmm.. well I downloaded the E00 file and inspected it with ogrinfo:

ogrinfo -al svc_hwd.e00 | less

... it looks like the export was from a converage which is a lot like the 
GRASS format with points lines boundaries all contained in the same file. in 
addition it looks like the groundwater information is stored in the polygon 
(contour) centroids, in the file called 'LAB' ... 

I think that the way to approach this would be to first import the countour 
boundaries, then import the centroids, then merge the centroids with the 
boundaries -- making areas. Then it might be possible to transfer the area 
attributes to the boundaries (lines) and then perform the interpolation on 
these new lines.

when working with E00 files, use a new version of GDAL or the acv- utilitites:
http://avce00.maptools.org/avce00/index.html

example:

# convert e00 to coverage with avc utils:
http://avce00.maptools.org/avce00/index.html

# convert e00 file to shapefiles with ogr2ogr:
# note that this will create a shapefile for each geometry type
ogr2ogr scv_hwd.shp scv_hwd.e00

CNT.dbf  CNT.shx  LAB.shp  PAL.dbf  PAL.shx   scv_hwd.shx
CNT.shp  LAB.dbf  LAB.shx  PAL.shp  scv_hwd.dbf  scv_hwd.shp

check the list archives for converting between geometry types, as I am a 
little rusty.

Dylan

On Thursday 22 February 2007 10:40, Moskovitz, Bob wrote:
> Hello Dylan,
>
> Me and my family has been sick too.  Just got back from work yesterday.
>
> Below is the data that I am trying to use in my project.  It comes from the
> Santa Clara Valley Water District.  I haven't contacted them about getting
> this data in another form because I have a lot of data in e00 format and I
> would really would like to figure out how to work with it.
>
> Just to refresh your memory, what I want to do with this data is to produce
> a raster groundwater map from the contours.  Can you look at this data and
> see if you can come up with a groundwater map?
>
> I hope you can help me :-)
>
> TIA,
> Bob
>
>
>
> -----Original Message-----
> From: Dylan Beaudette [mailto:dylan.beaudette at gmail.com]
> Sent: Tuesday, February 13, 2007 11:09 AM
> To: Moskovitz, Bob
> Subject: Re: [GRASS-user] Creating a ground water from a vector files of
> contours?
>
>
> Hi Bob,
>
> i have been sick the last couple of days and have not had a chance to look
> over my email.
>
> For starters, I would suggest getting the source data -- i.e. who has
> packaged the contours as an E00 file ? It would be good to find out as this
> format is a major pain to use in most cases.
>
> Cheers,
>
> Dylan
>
> On Tuesday 13 February 2007 09:31, Moskovitz, Bob wrote:
> > Hi Dylan,
> >
> > In case you missed my email, I thought I'd resend it.
> >
> > Bob
> >
> > -----Original Message-----
> > From: grassuser-bounces at grass.itc.it
> > [mailto:grassuser-bounces at grass.itc.it]On Behalf Of Moskovitz, Bob
> > Sent: Wednesday, February 07, 2007 5:01 PM
> > To: dylan.beaudette at gmail.com
> > Cc: grassuser at grass.itc.it
> > Subject: RE: [GRASS-user] Creating a ground water from a vector files of
> > contours?
> >
> >
> > Hi Dylan,
> >
> > I re-imported my data as lines.  When I query the boundary, I see that it
> > does not have the parameter DWT(the attribute I want to contour), but the
> > area does (see 1 below).  When I re-import my data as lines, DWT does not
> > get transferred to the lines (see 2 below).  Do you know of a way to give
> > my line features the DWT attribute?
> >
> > Bob
> >
> > ################### 1 ###################
> >
> > v.what -a map=scv_hwd_e00_area east_north=1594256.84694,320452.864286
> > distance=29.3609228972
> >
> > East: 1594256.84694
> > North: 320452.864286
> > Map: scv_hwd_e00_area
> > Mapset: PERMANENT
> > Boundary
> >
> > length 3900.000000
> > Layer: 2
> > Category: 122
> > driver: sqlite
> > database: /home/bobm/Data/Grass/cal3nad27/PERMANENT/cal3nad27.db
> > table: scv_hwd_e00_area_2
> > key column: cat
> > cat : 122
> > UserId : 0
> > FNODE_ : 534
> > TNODE_ : 534
> > LPOLY_ : 41
> > RPOLY_ : 2
> >
> > v.what -a map=scv_hwd_e00_area east_north=1594116.09055,320345.621324
> > distance=29.3609228972
> >
> > East: 1594116.09055
> > North: 320345.621324
> > Map: scv_hwd_e00_area
> > Mapset: PERMANENT
> > Object type: Area
> > Sq Meters: 662500.000
> > Hectares: 66.250
> > Acres: 163.703
> > Sq Miles: 0.2558
> > Layer: 1
> > Category: 40
> > driver: sqlite
> > database: /home/bobm/Data/Grass/cal3nad27/PERMANENT/cal3nad27.db
> > table: scv_hwd_e00_area_1
> > key column: cat
> > cat : 40
> > ValueId : 99
> > PolyId : 41
> > AREA : 662500
> > PERIMETER : 3900
> > SCV_HWD_ : 41
> > SCV_HWD_ID : 99
> > DWT : 35
> >
> > ################### 2 ###################
> >
> > v.what -a map=scv_hwd_e00_line east_north=1594256.84694,320449.512944
> > distance=29.3609228972
> >
> > East: 1594256.84694
> > North: 320449.512944
> > Map: scv_hwd_e00_line
> > Mapset: PERMANENT
> > Line
> >
> > length 3900.000000
> > Layer: 1
> > Category: 122
> > driver: sqlite
> > database: /home/bobm/Data/Grass/cal3nad27/PERMANENT/cal3nad27.db
> > table: scv_hwd_e00_line
> > key column: cat
> > cat : 122
> > UserId : 0
> > FNODE_ : 534
> > TNODE_ : 534
> > LPOLY_ : 41
> > RPOLY_ : 2
> >
> >
> >
> > -----Original Message-----
> > From: Dylan Beaudette [mailto:dylan.beaudette at gmail.com]
> > Sent: Wednesday, February 07, 2007 1:51 PM
> > To: Moskovitz, Bob
> > Cc: grassuser at grass.itc.it
> > Subject: Re: [GRASS-user] Creating a ground water from a vector files of
> > contours?
> >
> >
> > Hi Bob,
> >
> > Glad to hear you are closer to a solution. v.surf.rst *should* be able to
> > use contour data (referred to as isoline data in the manual). it sounds
> > like your contours were imported as polygons, which would result in
> > centroids being present.
> >
> > Either re-import your data as lines, or convert to lines. I am not sure
> > that converting areas to lines will preserve the connection between
> > contour and elevation attribute. Perhaps others on the list can provide
> > some feedback on this. For starters post the results of :
> > v.info your_contour_vector
> >
> > Alternatively, as Hamish suggested you might try out r.surf.contour --
> > note that this does not use the RST interpolator and has some limitation
> > with respect to NULL values. Also it only produces integer grids.
> >
> > Cheers,
> >
> > Dylan
> >
> > On Tuesday 06 February 2007 15:23, Moskovitz, Bob wrote:
> > > Hi Dylan,
> > >
> > > Looks like I was asking the computer to eat more then it can chew :-) 
> > > I have tried a smaller area and v.surf.rst did finish in good time. 
> > > Now I have another problem.  v.surf.rst seem to ignore the contours,
> > > but it noticed the centroids.  I see a bunch of bulls-eyes all over my
> > > map.  I guess I have missed a step?
> > >
> > > Bob
> > >
> > > -----Original Message-----
> > > From: Dylan Beaudette [mailto:dylan.beaudette at gmail.com]
> > > Sent: Monday, February 05, 2007 1:39 PM
> > > To: grassuser at grass.itc.it
> > > Cc: Moskovitz, Bob
> > > Subject: Re: [GRASS-user] Creating a ground water from a vector files
> > > of contours?
> > >
> > >
> > > Hi Bob,
> > >
> > > What have you defined your region as: i.e. what is the cell size, and
> > > what sort of area are you dealing with? If the cell size is too small,
> > > or your have defined a very large area, then v.surf.rst will take a
> > > very long time -- possibly producing a finer grid than really needed.
> > >
> > > That aside, contour data can sometimes be a troublesome source for an
> > > interpolation. Also, for VERY large datasets (small resolution / large
> > > area) you might try some other interpolator. check the archives for
> > > some ideas.
> > >
> > > Cheers,
> > >
> > > Dylan
> > >
> > > On Monday 05 February 2007 12:50, Moskovitz, Bob wrote:
> > > > Hello Grassusers,
> > > >
> > > > Like the subject line says, I need help creating a ground water map
> > > > using a vector file of contours.  The ground water file came from a
> > > > E00 file that was read into Grass using v.in.e00.  I am currently
> > > > running v.surf.rst which is taking a long time to run.  Are there
> > > > other ways to do this problem?
> > > >
> > > > Thanks in advance,
> > > > Bob
> > > >
> > > > Bob Moskovitz
> > > > Seismic Hazards Zonation Program
> > > > California Geological Survey
> > > > http://gmw.consrv.ca.gov/shmp
> > > >
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-- 
Dylan Beaudette
Soils and Biogeochemistry Graduate Group
University of California at Davis
530.754.7341