problem with stockspec function

I am getting the error:

Undefined function or method 'stockspec' for input arguments of type 'double'.

The function I am using is:

StockSpec = stockspec(sigma,Assetprice)

i checked v = ver; any(strcmp('Financial Derivates Toolbox', {v.Name}))

And got 0

Can I replace 'Stockspec' with another function? Or can I get that Toolbox? Please Help I need soo badly that function

[Geoff Hayes]

You may want to think about purchasing the Financial Derivatives Toolbox (this toolbox seems to have been replaced with the Financial Instruments Toolbox as of R2012b), or try to request a trial license. You would need to contact The MathWorks directly.