GRASS 7 - raster calculator "and"

Question

I am struggling with one thing in the raster calculator in GRASS GIS 7: I want to create a raster_b from raster_a, with raster_a values between >=-0.15 and <=0.15. The raster containing values <-0.15 I calculated with if("raster_a" >0.05 , raster_b, null()),

but how do If((raster_a >-0.15) and (raster_a <0.15), raster_b, null))?

Any help is appreciated! Peter

Answer 1

The formulation is (for GRASS 6.x and GRASS 7):

if expression = True -> value of raster_a  
if expression = False -> nothing (null())

and:

resulting_layer = (expression, True, False)

so:

raster_b = (if..., raster_a, null())

• In the GRASS shell:

  r.mapcalc 'raster_b = if(raster_a > -0.15 && raster_a <0.15 ,raster_a,null())'

• with the Raster Map Calculator: