--> //initializations

--> q=100 //l/sec (rate of flow)
 q  = 

   100.


--> r2=25 //m (water table)
 r2  = 

   25.


--> r1=3 //m (water table)
 r1  = 

   3.


--> R=8.5 //m (water table in sandy layer)
 R  = 

   8.5


--> R1=3 //m (drawdown of water table)
 R1  = 

   3.


--> R2=0.5 //m (drawdown of water table)
 R2  = 

   0.5


--> //calculations

--> Q=q/1000 //(rate of flow)
 Q  = 

   0.1


--> z1=R-R1 //(height of cylindrical surface)
 z1  = 

   5.5


--> z2=R-R2 //(height of cylindrical surface)
 z2  = 

   8.


--> k=(Q*log(r2/r1))/(%pi*((z2^2)-(z1^2))) //(coefficient of permeability)
 k  = 

   0.0019997


--> //results

--> printf('coefficient of permeability=%f',k) //m/sec
coefficient of permeability=0.002000
