previous array element value?

• 04/26/2021 at 3:25 PM #168075
  pableitor

  Any idea how to get an arrays variable previous value ?  For instance, I tried this silly code:

  $x[0] = close return $x[0][1]

  1 2	$x[0] = close return  $x[0][1]

  but $x[0][1] which is supposed to be the old value returns the present value same as $x[0] 

  

  pableitor

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  04/26/2021 at 3:43 PM #168078
  robertogozzi

  It’s not allowed because arrays are not historicized, unlike common variables which allow to see previously  retained values.

   

   

  

  robertogozzi

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  04/26/2021 at 3:55 PM #168080
  robertogozzi

  IF you have an array and want to historicize a very few elements, say elements 1  and 4, you can write:

  $Element[0] = close //$Element[0][1] is not allowed $Element[1] = high //$Element[1][1] is not allowed $Element[2] = close //$Element[2][1] is not allowed $Element[3] = low //$Element[3][1] is not allowed $Element[4] = range //$Element[4][1] is not allowed a = $Element[1] //a[1], a[2], ... is allowed to see the history of Element[1] b = $Element[4] //b[1], b[2], ... is allowed to see the history of Element[4]

  1 2 3 4 5 6 7

  $Element[0] = close //$Element[0][1] is not allowed $Element[1] = high  //$Element[1][1] is not allowed $Element[2] = close //$Element[2][1] is not allowed $Element[3] = low   //$Element[3][1] is not allowed $Element[4] = range //$Element[4][1] is not allowed a = $Element[1]     //a[1], a[2], ... is allowed to see the history of Element[1] b = $Element[4]     //b[1], b[2], ... is allowed to see the history of Element[4]

  (unless you want to use a1, a2, a3,… a1000, provided you have enough time and memory).

   

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  pableitor

  

  robertogozzi

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  04/26/2021 at 3:56 PM #168081
  pableitor

  ok, maybe they reserve the format $x[i][j] for future 2-D arrays.  Yes, I found a simple workaround by using  temp variables like you said, but it takes  memory and time for long vectors:

  $x[0] = open $x[1] = close ... a = $x[0] b = $x[1] ... return a[1], b[1],...

  1 2 3 4 5 6 7 8 9 10

  $x[0] = open $x[1] = close   ...   a = $x[0] b = $x[1] ...   return  a[1], b[1],...

   

  

  pableitor

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  04/26/2021 at 4:21 PM #168084
  Nicolas

  Historizing arrays would have take more memory than this workaround, considering that the current one dimension array can handle one million column! 🙂

  

  Nicolas

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