'Genrate several arch processes
for !1=1 to 5
smpl 1 100
genr white!1=nrnd
for !2=1 to 5
genr alpha0!2=1
genr alpha1!2=.8
genr phi!2=.2*!2
smpl 1 1 
genr archerr=0
genr archy!1!2=0
smpl 2 100
genr archerr=white!1*@sqr(alpha0!2+alpha1!2*archerr(-1)^2)
genr archy!1!2=.2*archy!1!2(-1) +archerr
next
next

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