Automatic ARMA selection

Hello!
I want to change the program beacuse I need a regression without constant. I stablished a conditional, but it does't work.

Code:

'Create some data.  Delete these first few lines if you want to run on your existing workfile.

series y_SW =0
copy  etec y_SW


'Program that calculates the "best" ARMA specification for an equation.  Edit the variables below to match your particular data/setup.

%eqname = "ciclo_SW"   'name of equation object that will be used.
%maxAR = "4"           'maximum number of AR terms
%maxMA = "4" 'maximum number of MA terms
%dep = "Y_SW"   'dependent variable
%regs = "C "   'independent variables
%criterion = "@schwarz"    'which criterion to use  enter "@AIC" for Akaike, "@schwarz" for Schwarz, and @HQ for Hannan-Quinn

!maxAR = @val(%maxAR)
!maxMA = @val(%maxMA)


close {%eqname}


'create table for storing critical values.
%matname = "crits_SW"
if @isobject(%matname) then 
   %matname = "__crits_SW"
   if @isobject(%matname) then
      delete {%matname}
   endif
endif
table(!maxar+2,!maxma+2) {%matname}
{%matname}(1,1) = "AR /  MA"
{%matname}.setlines(1) +b
{%matname}.setlines(a) +r

'set sample
smpl @all

!mincrit = 1e12  'set the minimum to an artificially large value to begin

'estimate the models
%arstring = ""
for !i=0 to !maxar
   'build up string for AR terms.
   if !i>0 then
      %arstring = %arstring + " ar(" + @str(!i) + ")"
   endif

%mastring = ""
   for !j=0 to !maxma
      'build up string for MA terms
      if !j>0 then
         %mastring = %mastring + " ma(" + @str(!j) + ")"
      endif

      'estimate equation
if %arstring="ar(1)" or %arstring="ar(2)" or  %arstring="ar(3)" or  %arstring="ar(4)" or %mastring="ma(1)" or %mastring="ma(2)" or %mastring="ma(3)" or %mastring="ma(4)"  then
       equation {%eqname}.ls(arma=cls, optmethod=legacy) {%dep} {%arstring}{%mastring}
endif

if %arstring="ar(0)" and  %mastring="ma(0)" then
      equation{%eqname}.ls(arma=cls, optmethod=legacy) {%dep} {%regs}
endif
      'capture criterion
      if @upper(%criterion) = "@SCHWARZ" then
         !crit = {%eqname}.@schwarz
      endif
next
next

I have an error because %eqname is undeterminated or undifined. I think last conditionals isn't correct but I don't know why.

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