[GRASSLIST:2140] RE: r.reclass: how to reclass only part of the c ategories

CHAN Kenneth ken.chan at tenix.com
Sun Jul 22 21:49:12 EDT 2001

> Subject: [GRASSLIST:2131] r.reclass: how to reclass only part of the
> categories
> I've downloaded some GLOBE DEM files, and I would like to use 
> them in nviz. 
> The problem is that some areas (such as the polders in 
> Holland) have values 
> around 65500, making it difficult to use the files in nviz 
> due to the extreme 
> differences in values. I would therefore like to reclass them 
> in order to give 
> them all a value of -1.
> Now r.reclass allows me to either use reclass rules, but then 
> I would have to 
> write a reclass rule for evey point between 0 and 9000 (the 
> ones I want to 
> keep the way they are) since if I don't do it, r.reclass will 
> class them all 
> as NULL. And if I use the r.reclass interface, I would have 
> to do all the 
> changes to -1 by hand.
> So my question: is there a reclass rule meaning something 
> like 'leave 1 thru 
> 9000 the way they are' ?

If you don't mind changing the "out of range" values to 0 instead to -1, you
can try something like:
r.rescale input=inputmap from=1,9000 output=outputmap to=1,9000


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