Problem in monte carlo simulation from ocean

Hi,

I am trying to run monte carlo simulation from ocean but I am struggling a bit with monteExpr(). I am using IC 6.1.7. My ultimate goal is to do trim montecarlo simulation . 

How can I do  calculation in montecarlo e.g calculate a value of resistor in dc operating point simulation.

analysis('dc ?saveOppoint t )
desVar( "vdda" 1 )
desVar( "vin" 0.45 )
envOption(
'analysisOrder list("dc")
)
save( 'v "/vin" )
save( 'i "/R0/plus" "/R1/plus" )
temp( 27 )

monteCarlo( ?numIters "10" ?startIter "1"
?analysisVariation 'process ?sweptParam "None" ?sweptParamVals "27" ?saveData t
?nomRun nil ?append nil ?saveProcessParams t
)

monteDisplay()

;-------------------------Problem statement------------------
monteExpr("Vx" "VDC("/vin")") 

monteRun()

Regads,

Ralph