cell counts for a certain value range in strds

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cell counts for a certain value range in strds

Veronica Andreo
Hi all, 

maybe another of my silly questions, but is there a straightforward way of getting cell counts for a certain range of values for a subset of maps in a strds? 

I've used this to get the list of maps that meet the condition i'm interested in:

t.rast.list input=cla@clorofila columns=name,start_time,end_time,min,max where="max > 65.0" > maps_max_65

but now i want to know how many cells in each one of those maps actually meet that condition. I could use t.rast.extract, then reclassify in two categories, set the one i'm interested in to null and then t.rast.univar; but is there a more straighforward way to do that? Something like r.report units=c or r.stats -c, but with a where clause??? i'm lazy, i know... and it's nap time here... friday... :P

All the best, 
Vero

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Re: [kinda solved] cell counts for a certain value range in strds

Veronica Andreo

Dear all,

Dismiss my previous email :)

I've overlooked the expression parameter in t.rast.extract. I kinda solved my problem (kinda because it's not as straightforward as i'd like) with:

t.rast.extract input=cla output=cla_max65_extract basename=cla_max65 where="cla > 65.0" expression="if (cla>65.0,1,null())"

t.rast.univar -eh cla_max65_extract  > bla

And then, R or whatever to do "cells - null_cells" and there i have the number of cells with values higher than 65 :)

Have a great weekend!

vero

Ps: cla stands for chlorophyll-a, my strds

El 09/05/2014 15:37, "Veronica Andreo" <[hidden email]> escribió:
Hi all, 

maybe another of my silly questions, but is there a straightforward way of getting cell counts for a certain range of values for a subset of maps in a strds? 

I've used this to get the list of maps that meet the condition i'm interested in:

t.rast.list input=cla@clorofila columns=name,start_time,end_time,min,max where="max > 65.0" > maps_max_65

but now i want to know how many cells in each one of those maps actually meet that condition. I could use t.rast.extract, then reclassify in two categories, set the one i'm interested in to null and then t.rast.univar; but is there a more straighforward way to do that? Something like r.report units=c or r.stats -c, but with a where clause??? i'm lazy, i know... and it's nap time here... friday... :P

All the best, 
Vero

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