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; MODEL1.PRO           ; The name of this program, should I forget it.
DATAFILE='MODEL1.DAT'  ; File name is a string marked with: '
X=DBLARR(1000)         & Y=X        & N=0
OPENR,1,DATAFILE       & WHILE NOT EOF(1) DO BEGIN & Q=DBLARR(2)
READF,1,Q & X(N)=Q(0)  & Y(N)=Q(1)  & N=N+1   & ENDWHILE   & CLOSE,1
J=WHERE(X GT 0.)       & X=X(J)     & Y=Y(J)
END                    ; Every IDL program ends with the command END
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