[kepler-dev] Reg. calling functions from expressions

[Sivagowri Swaminathan]

Hi
I am a beginner and so tried to do some samples given in the ptolemy docs.
I had a constant actor where I typed a function function(x:int) x^2.
I have a ramp actor which increases in steps of 1.
I connected the output of both the actors to an expression actor (i created 
two input ports for this and named them f and y). Inside the expression, I 
typed f(y). The output of expression is conn to a display. I have a SDM 
which is set to manage 20 iterations. When I ran, I get the following error 
msg:

'wrong number of indices when referencing f' from the expression actor.
The function takes only one input parameter. The ramp actor provides the y 
values to expressions, which the latter uses to compute the function.

can somebody help me out with this?

Thanx
siva