[GRASS-user] r.mapcalc problem ?

[Martin Laloux]

Excuse me if I seem stupid but I have a problem with r.mapcalc. I have a dem
stored in FCELL with range of data(z) : min = -26.670000  max = 695.960022 .
I try to extract a raster/dem with all values < 0.
I try
r.mapcalc 'test = if(mydem >0.0000,mydem,null())'
Results give me
Range of datafor test :    min = 0.200000  max = 695.960022
with r.mapcalc 'test = if(mydem < 0.0000,mydem,null())'
results
Range of data:    min = -26.670000  max = -0.010000  -> ok for me
But when i  display test map, i allways get the full dem and not only a map
with values < 0.
I try replacing test with MASK but same result
What is the error I made or how can I do ?
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