Checking conditions in an indicator

• 05/09/2019 at 2:01 PM #98079
  robertogozzi

  I wrote an indicator to signal when a price crosses over the middle line (50) of RSI for the first time, but the code I wrote always returns 0 (pic 1):

  IF BarIndex < 1 THEN MyCond = 0 ENDIF MyRsi = Rsi[14](close) IF MyCond = 0 THEN MyCond = MyRsi CROSSES OVER 50 ENDIF RETURN MyCond

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  IF BarIndex < 1 THEN    MyCond = 0 ENDIF MyRsi = Rsi[14](close) IF MyCond = 0 THEN    MyCond = MyRsi CROSSES OVER 50 ENDIF RETURN MyCond

  I could find this workaround, by adding a dummy condition to test if MyCond=1 (pic 2):

  IF BarIndex < 1 THEN MyCond = 0 ENDIF MyRsi = Rsi[14](close) IF MyCond = 1 THEN ELSE MyCond = MyRsi CROSSES OVER 50 ENDIF RETURN MyCond

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  IF BarIndex < 1 THEN    MyCond = 0 ENDIF MyRsi = Rsi[14](close) IF MyCond = 1 THEN ELSE    MyCond = MyRsi CROSSES OVER 50 ENDIF RETURN MyCond

  Why this behaviour (both on v10.3 and beta v11)?

   

   

   

   

  

  robertogozzi

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  05/09/2019 at 3:02 PM #98086
  Nicolas

  I made a report too.

  

  Nicolas

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  05/09/2019 at 3:05 PM #98087
  pableitor

  It seems that from barindex = 0 to 14  the RSI(14) value is undefined. Just do like this:

  IF BarIndex < 15 THEN MyCond = 0 ENDIF MyRsi = Rsi[14](close) IF MyCond = 0 THEN MyCond = MyRsi CROSSES OVER 50 ENDIF RETURN MyCond

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  IF BarIndex < 15 THEN    MyCond = 0 ENDIF MyRsi = Rsi[14](close) IF MyCond = 0 THEN    MyCond = MyRsi CROSSES OVER 50 ENDIF RETURN MyCond

   

  

  pableitor

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  05/09/2019 at 3:59 PM #98095
  Vonasi

  pableitor wrote:

  It seems that from barindex = 0 to 14  the RSI(14) value is undefined.

  This was my first thoughts but even if it is undefined then it should just be a case that myCond = 0 and there is no cross of RSI over 50 during the first 14 bars so MyCond should remain at zero but then once the RSI does have a defined value after 14 bars then MyCond should change to a value of 1 once the first cross of 50 happens – but it never changes.

  

  Vonasi

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  05/09/2019 at 3:59 PM #98096
  robertogozzi

  I can also work it out by clearing MyCond everytime (same as IF BarIndex < 9999999 THEN) :

  MyCond = 0 MyRsi = Rsi[14](close) IF MyCond = 0 THEN MyCond = MyRsi CROSSES OVER 50 ENDIF RETURN MyCond

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  MyCond = 0 MyRsi = Rsi[14](close) IF MyCond = 0 THEN    MyCond = MyRsi CROSSES OVER 50 ENDIF RETURN MyCond

  but it’s not what I need to do.

  Thank you.

  

  robertogozzi

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  05/22/2019 at 10:58 AM #99146
  Nicolas

  Here is the fixed code:

  IF BarIndex < 1 THEN MyCond = 0 ENDIF MyRsi = Rsi[14](close) IF MyCond = 0 and barindex >= 14 THEN MyCond = MyRsi CROSSES OVER 50 ENDIF RETURN MyCond

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  IF BarIndex < 1 THEN MyCond = 0 ENDIF MyRsi = Rsi[14](close)   IF MyCond = 0 and barindex >= 14 THEN MyCond = MyRsi CROSSES OVER 50 ENDIF   RETURN MyCond

  The problem is that the code tries to check the MyRsi CROSSES OVER 50 condition if the barindex is equal to 1.
  But at this moment there is not enough candlestick to calculate RSI.
  So it returns that mycond = NaN (Not a Number)
  And then we never go back into the loop because IF MyCond = 0 is never true.

  1 user thanked author for this post.

  robertogozzi

  

  Nicolas

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  05/22/2019 at 11:03 AM #99148
  robertogozzi

  Great Nicolas, thank you!

  

  robertogozzi

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  05/22/2019 at 1:50 PM #99164
  GraHal

  So there is no way in an Indicator to have preloadbars?

  This will answer a problem I was having with an Indicator a few days ago.

  

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