[GRASS-user] (no subject)

[Ned Horning]

Markus,

Thanks for the feedback. The advice is very helpful. I've been slowly getting
used to GRASS but still have a way to go. If I can stick with it I hope to learn
enough to create a week-long "GRASS for conservation" workshop that we can offer
at our research station in southeastern Arizona and in our projects in SE Asia.


Here are some clarifying remarks and a few more questions if anyone can help.

> It will work. Everything takes time but I don't expect problems. GRASS 6.2

> has been used for >10GB images, since then more testing and fixing
> happened. Best is to use the latest 6.4.0RC2 version.
>   
I'll see if I can get this version set up so it doesn't conflict with the GRASS
version bundled with QGIS. My linux (Ubuntu) skill are also still quite poor
but I'm learning (again).
>> 4) Georeference shrub / non-shrub map to reference Landsat images [might
do
>> this with ENVI or ERDAS unless GRASS is a good choice]
>>     
>
> Also unclear to me: above you say that you generate the shrub / non-shrub
map
> in GRASS, then it is already geocoded. Or not?
>   
Sorry - I wasn't very clear. The images I'm working with are geocoded but the
image-to-image registration is poor. I plan to project all of the images into
the same projection (some are in UTM and some use different datums) and then
do an image-to-image registration. I wasn't sure if GRASS would be an efficient
tool to do the image-to-image registration. I should just try it.
>   
>> 5) Create percent shrub cover map using regression tree algorithm, Landsat
imagery,
>> and shrub location  data from the high resolution shrub / non-shrub map.
I will
>> probably do this using proprietary software unless I can do it easily in
GRASS
>> since a method has been established for another project.
>>     
>
> Of course GRASS-R-extention comes to mind for all kinds of statistics.
I'm considering using GRASS for this but would like to know if anyone has used
GRASS with R as the regression tree engine. I have a vague recollection of someone
doing this several years ago but didn't find anything after a quick search.
I suppose it would require getting training data from GRASS to R to generate
the regression tree and then port the tree results back to GRASS to apply the
rules to the dataset. It would be great if an interface already existed to do
this but if not I can probably figure it out. I'm just not sure how long it
will take me.

All the best, 

Ned