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6206 :: ipopt - Problem with Macro

• mantielero (orginal) [2020-04-13T20:01:09+02:00] view original

  I am having an issue with a macro that I am not managing to solve.

  The code is messy, but I will try to make clear the issue.

  I have the source code here. When I compile this code, the last lines displayed (from expandMacro):

  echo [repr [[2.0 * x[3]], [x[3], 0.0], [x[3], 0.0, 0.0],
            [2.0 * x[0] + x[1] + x[2], x[0], x[0], 0.0]]]

  created by this lines.

  Basically, obj_hess is typed as seq[seq[NimNode]] and contains a triangular matrix:

  [ [2.0 * x[3]],
    [x[3],                         0.0],
    [x[3],                         0.0,       0.0],
    [2.0 * x[0] + x[1] + x[2],     x[0],      x[0],       0.0]]]

  The problem is when I reference a particular line or item. If I do the following in line 474:

  echo repr `obj_hess`[0]

  I get the following error:

  /home/jose/src/ipopt.nim/src/ipopt.nim(547, 3) template/generic instantiation of `problem` from here
  /home/jose/src/ipopt.nim/src/ipopt.nim(323, 15) Error: type mismatch: got <array[0..1, Number]> but expected 'array[0..0, float]'

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• spip (orginal) [2020-04-13T20:28:56+02:00] view original

  Have you tried writing it

  echo repr(`obj_hess`[0])
  Run

  ?

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• mantielero (orginal) [2020-04-13T20:43:45+02:00] view original

  It doesn't work either. But bear in mind that this is a simplification. That line will get replaced by somethin like:

  for row in `obj_hess`:
    for item in row:
      values[idx] = obj_factor * item
      idx += 1
  Run

  Which is not working.

  It is very strange, because I am using something similar here and it is working. That is what is making me thing that this is an error a not a bug.

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• DeletedUser (orginal) [2020-04-14T01:19:49+02:00] view original

  Arrays cannot contain arrays of different sizes, you have to use seqs or just a 1 dimensional array that you treat as 2 dimensional. This is because the arrays [1] and [1, 2] are different types.

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