What’s the correct way of getting previous values of an indicator?

• 07/06/2022 at 3:35 PM #196898
  xbldevbb

  Hi all

  I’m trying to get the values of previous bars of an indicator, and this is what I’m trying to do:

  ema100 = ExponentialAverage[100](close)

  ema100_20barsbefore = ema100[20]

  Is this correct?

  Also how do I check if an indicator actually has a value at a certain point? Like at the start of the day maybe some indicators don’t have values yet, and if I do indicator[20] its value maybe invalidate because of that.

   

  

  xbldevbb

  Participant

  Topics: 4

  Replies: 2

  Been thanked: 0 times
  07/06/2022 at 6:55 PM #196918
  robertogozzi

  Your code is correct.

  I am not sure I understood your second question. If you check your chart you will spot the value retained now by any variable and the one of the 20th previous bar. Is this what you meant?

   

  1 user thanked author for this post.

  xbldevbb

  

  robertogozzi

  Moderator

  Topics: 69

  Replies: 17601

  Been thanked: 4322 times
  07/07/2022 at 3:31 PM #196981
  xbldevbb

  Thanks <span class=”bbp-author-name”>robertogozzi</span>

  What I mean by 2nd question is that, sometimes an indicator may not have values.

  For example,  ExponentialAverage[100](close) don’t have values for the initial bars, not sure if it’s exactly 100 bars or some other value. If you move your mouse cursor to the bars in the beginning, in the values displayed(open, close etc) it doesn’t have a value. Not sure if this is something I’m doing wrong.

  And the weird thing is, when I try make a simple indicator that checks if some indicator has value, such as ema100 > 0, it correctly detects that at first the indicator doesn’t have value for certain number of bars. But when I try to use the exact checking logic to do backtest, it would generate orders at bars where clearly there’s no indicator value.

   

  

  xbldevbb

  Participant

  Topics: 4

  Replies: 2

  Been thanked: 0 times
  07/09/2022 at 10:43 AM #197050
  robertogozzi

  I think this is due to the fact that ProOrder and ProBackTest preload form 2000 bars (default)  up to 10K bars. Try using this line at the beginning of your code:

  DEFPARAM PreLoadBars = 0 //10000 max allowed

  1	DEFPARAM PreLoadBars = 0   //10000 max allowed

   

  1 user thanked author for this post.

  xbldevbb

  

  robertogozzi

  Moderator

  Topics: 69

  Replies: 17601

  Been thanked: 4322 times
• Author
  Posts