[GRASS-user] [GRASSLIST:1120] Arc vs grass coming soon (unless someone wants to get it started)

M S mseibel at gmail.com
Mon Jun 19 17:36:47 EDT 2006


very cool.  i hope to contribute where i can.

On 6/19/06, Jonathan Greenberg <jgreenberg at arc.nasa.gov> wrote:
>
> Grassers:
>
>         I'll get the table started ASAP, but I'm busy over the next few
> weeks -- if someone wants to get it going on the wiki feel free, otherwise
> I'll get to it when can.  I was thinking a table at the top of the page
> with
> the headings "Software (ARCINFO/ArcMap/ArcView)","ESRI command/feature",
> "GRASS command(s)", and an anchor-link to a set of headers below the table
> that have a discussion of the similarities/differences, and how to
> replicate
> the arc process "perfectly" if possible.  The table and subsequent
> discussion should be alphabetized by the ARC software and then by the arc
> command.  Here's an example/possible entry that could be included:
>
> ***
>
> Table entries:
> Software: ARC/INFO (ARC)
> ESRI command/feature: LATTICESPOT
> GRASS command(s): v.what.rast
>
> Discussion entry:
> LATTICESPOT
> LATTICESPOT has a nearly perfect translation to v.what.rast as follows:
> LATTICESPOT <in_lattice> <in_cover> {spot_item} {z_factor}
>         translates to:
> v.what.rast vector=<in_cover> raster=<in_lattice> layer=layer
> column={spot_item}
>
> Discrepancies:
>         -{spot_item} defaults to "SPOT" for LATTICESPOT, but must be
> explicitly defined for v.what.rast
>         -{z_factor} must be applied the GRASS vector database
> after-the-fact.
>         -LATTICESPOT performs a bilinear interpolation to assign raster
> values to the output vector, whereas v.what.rast uses nearest neighbor.
>
> ***
>
> One of the goals of this wiki page, I think, would be to minimize or
> remove
> all discrepancies.  This is where the use of a wiki really helps: power
> users of GRASS can offer ways that people like me (who are basically
> newbies) can't figure out.  For instance, how can we solve the z_factor
> discrepancy -- how do I multiply a GRASS vector column by a fixed value?
> This would remove that discrepancy between the ARC and GRASS.
>
> --j
>
> --
>
> Jonathan A. Greenberg, PhD
> NRC Research Associate
> NASA Ames Research Center
> MS 242-4
> Moffett Field, CA 94035-1000
> Phone: 415-794-5043
> AIM: jgrn3007
> MSN: jgrn3007 at hotmail.com
>
>
> _______________________________________________
> grassuser mailing list
> grassuser at grass.itc.it
> http://grass.itc.it/mailman/listinfo/grassuser
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.osgeo.org/pipermail/grass-user/attachments/20060619/2cfdccfa/attachment.html


More information about the grass-user mailing list