[GRASSLIST:3297] r.volume help

[Anil Kumar Bhagat]

Dear GRASS Users,
                  I want to calculate the depth of a lake . For that, I
have generated the DEM map from contour data . Now to calculate the Volume 
, I am runing the module <r.volume> I am giving the following input for
<r.volume>

1) DEM map 
2) output map from r.clump ( The input for  r.clump I am using the
DEM map and I am getting one output map )

the module is runing but it is showing all the volume 0.00 

May I get help in the regard .

With Warm Regard
 
Anil Kumar Bhagat
( Project Asst. )
Center For Ecological Science ,
Indian Institute Of Science Banglore,
Banglore .
Phone : 3600985 ,3092506 ext-213