Re: [om-users] raster file converter

[Tim S. <ti...@li...>]

Hi

On 1/23/07, Peter Brewer <p.w...@re...> wrote:
> Dear Laura,
>
> The main developer (Tim) is currently soaking up the sun in South Africa, so
> let me see if I can help.
>

Yes - I got quick access to the internet so I'll answer what I can now
and the rest when I return to Brazil...

> Let me recap your main questions:
>
> 1) Is it possible to run GARP many times and is oM scriptable?
> 2) Is it possible to use an ArcView DEM as an input layer (or mask layer) in
>  oM?
> 3) Is it possible to export the output map for use in ArcView?
>
> Answers:
>
> 1) First of all, yes - oM is scriptable.  The desktop program you are using is
> just one (user friendly!) method of running models with the oM library.  As
> well as various programming interfaces (to use oM as part of other programs)
> there is a command line interface which allows you to script your own
> experiments.  Take a look at the documentation on the oM website and then
> Renato is probably your best bet for answering any questions you have.
>
> The other option is to use the 'Algorithm Manager' in oM Desktop.  This
> enables you to create your own algorithm profile modified to your needs.
> This enables you to create a 'profile' where many runs of GARP can be done
> and then amalgamated into a single output map using the best subsets
> selection routine (described in many articles).  This may not be of much help
> though if you want to do your own jacknifing etc.  Adding re-sampling methods
> like jacknifing is however on the todo list for development.  If you plead
> nicely at Tim (and you're not in a huge hurry) you may be able to get it to
> the top of his list in time for your needs! ;-)
>

Right - this is a better & fuller response than the one that I posted
a few minutes ago...

> 2) oM uses the GDAL library for reading and writing raster layers.  As such it
> can use any raster format shown in the list at
> www.gdal.org/formats_list.html.

Ok there is one caveat here. The GDAL I compiled for the windows
openModeller Desktop installer does not include support for *all* the
listed formats above since many of them require esoteric and sometimes
proprietry libraries to be present on the developers system when
building. I tried to cover the 'typical' formats people will use. If
there are formats from the above list you need that are missing, I
will try to add support for them if you notify me via the bug
tracker...

The standard ESRI DEM format has not been
> opened up to the community so unfortunately it cannot be read directly in oM.
> The raster file converter in oM is also based on GDAL so is only useful for
> converting GDAL readable files into GeoTiffs or AI ASCII Grid files.  This is
> useful if you have lots of files in lots of different (GDAL) formats and you
> want to make them all uniform.  For you however, it's not very helpful!
>

There is a known bug with the file format convertor:

http://sourceforge.net/tracker/index.php?func=detail&aid=1636804&group_id=101808&atid=631036

I'll try to have it fixed in the next release.

> What you'll need to do is use the ArcToolbox to export your ESRI DEM into
> something a little more friendly for non-esri programs.  What format this can
> be will vary dramatically on which particular version of ArcGIS you have and
> also which level of licencing.  The best format is probably GeoTiff if you
> can see it somewhere in the mountain of options.
>
> 3) If you go to Edit > Preferences, you will see the 'data directory'
> and 'output format' settings for oM.  By default these are set to a folder
> called .omgui in your my docs and the output format set as ERDAS Imagine.
> You shouldn't have any problems reading the ERDAS files in ArcGIS without any
> conversion so it's just a matter of finding the files you are interested in.
> So... navigate to the .omgui/modelOutputs folder and you will find a bunch of
> funny folders.  These names correspond to the unique experiment code you'll
> see at the top of your experiment report.  Inside these you will find your
> ERDAS files and also shapefiles containing your input localities.
>
> Personally I think we should put in a feature request to have a button that
> outputs all the current experiment maps to a selected directory.  I think
> users are used to the idea that they go to File > Save to write their data to
> a folder of their choice. Perhaps this would be a good addition to oM
> Desktop?
>

Yup this sounds like a reasonable request. Ill prioritise its
implementation for the next release - thans for adding it to the
request queue.

>
> I hope this answers your most pressing questions!  Let me know if there is
> anything else I can help with.

Thanks Pete!

Regards

-- 
Tim Sutton

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