Hi!
Parabolic SAR needs high and low to be calculated.

calculo de parabolica sar

Here you have the code so you could make your own tests

// SAR - Parabolic SAR
//
// https://www.prorealcode.com/topic/parabolic-sar-code/page/2/#post-174049
//
//    Parameters:
//
SARinit  = 0.02
SARstep  = 0.02
SARlimit = 0.2
//
IF BARINDEX < 2 THEN
   parabolic = LOW
   islong    = 1
   af        = SARlimit
   hp        = HIGH
   lp        = LOW
ELSE
   IF islong THEN
      parabolic = parabolic + af * (hp - parabolic)
      parabolic = MIN(parabolic, LOW[1])
      parabolic = MIN(parabolic, LOW[2])
   ELSE
      parabolic = parabolic + af * (lp - parabolic)
      parabolic = MAX(parabolic, HIGH[1])
      parabolic = MAX(parabolic, HIGH[2])
   ENDIF
   reverse = 0
   IF islong THEN
      IF LOW < parabolic THEN
         islong    = 0
         reverse   = 1
         parabolic = hp
         lp        = LOW
         af        = SARinit
      ENDIF
   ELSE
      IF HIGH > parabolic THEN
         islong    = 1
         reverse   = 1
         parabolic = lp
         hp        = HIGH
         af        = SARinit
      ENDIF
   ENDIF
   IF NOT reverse THEN
      IF islong THEN
         IF HIGH > hp THEN
            hp = HIGH
            af = af + SARstep
            af = MIN (af,SARlimit)
         ENDIF
      ELSE
         IF LOW < lp THEN
            lp = LOW
            af = af + SARstep
            af = MIN (af,SARlimit)
         ENDIF
      ENDIF
   ENDIF
ENDIF
RETURN parabolic as "parabolic SAR"