Function GetC(L , a1 , PLoad , DLoad) 
   
    Lreal = L
    a1real = a1
    PLoadreal = PLoad
    DLoadreal = DLoad
        
 
    ' Get a reference to SmartSketch
    Set objSmartSketch = GetObject(, "SmartSketch.Application")

    ' Get a reference to the Mathcad object
    Set objmathcad = objSmartSketch.ActiveDocument.ActiveSheet.SmartFrames2d(1).object
   
    Call objmathcad.SetComplex("in0", Lreal, 0)
    Call objmathcad.SetComplex("in1", a1real, 0)
    Call objmathcad.SetComplex("in2", PLoadreal, 0)
    Call objmathcad.SetComplex("in3", DLoadreal, 0)

    Call objmathcad.Recalculate
    Call objmathcad.GetComplex("out0", flowreal, flowimag)
    GetC = flowreal
      
 End Function