[Gretl-users] function

Hello everybody, I tried to build my first gretl function with no much sucess. The exercise is very simple: write a function to obtain the theoretical simple correlations for an AR(2) process, depending only on two parameters phi1 and phi2. The following script works ok: --------------- nulldata 20 series y = 1.0 scalar phi1 = 0.4 scalar phi2 = 0.5 scalar rho1 = phi1 / (1-phi2) genr y[2] = rho1 genr y = phi1*y(-1)+phi2*y(-2) genr y1 = y(1) ------------ So the series y1 contains the theoretical correlations. I wrote the following script, based on the information of the manual, but the function does not work: -------- nulldata 20 # function definition function corrAR2 (scalar phi1, scalar phi2) series y = 1.0 scalar rho1 = phi1 / (1-phi2) genr y[2] = rho1 genr y = phi1*y(-1)+phi2*y(-2) genr y2 = y(1) return series y2 end function # function call (y1) = corrAR2 0.4 0.5 -------- Which is the problem? I tried it with official gretl-1.5.0 in mandrivalinux, and also with the current Windows snapshot. There were no errors or warnings and I obtained only a series with zeroes. -- Ignacio Díaz-Emparanza Dpto. de Economía Aplicada III (Econometría y Estadística) UPV-EHU