code 41545;
real procedure WEIBULL(X, LOC, SCALE, ALPHA);
value X, LOC, SCALE, ALPHA; real X, LOC, SCALE, ALPHA;
WEIBULL:= if SCALE ≤ 0
          then STATAL3 ERROR(“WEIBULL”, 3, SCALE)
          else if ALPHA ≤ 0
          then STATAL3 ERROR(“WEIBULL”, 4, ALPHA)
          else if X ≤ LOC then 0
          else 1 - EXP(-((X - LOC) / SCALE) ⭡ ALPHA);
eop