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5443 :: Nim equivilent of Python's slicing with step list[start: end: step]

• hugogranstrom (orginal) [2019-11-03T11:54:54+01:00] view original

  I'm trying to get a slice of a seq but I only want every second element. I could write a loop that does this but I'm wondering if there is a more elegant way of doing it? In Python you can do:

  Run

  I know that Arraymancer has this syntax: a[0.._|2] but is there any equivilent for normal seqs?

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• mratsim (orginal) [2019-11-03T12:03:38+01:00] view original

  There is none.

  Also if by sliced you meant that they share memory, it wouldn't be possible with normal seqs as they always copy (unless you use shallow() or you wrap them in an object with the {.shallow.} pragma like I do in Arraymancer)

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• hugogranstrom (orginal) [2019-11-03T12:05:53+01:00] view original

  Ok, good to know :-)

  Copy would have been fine but I'll return to my loop approch instead

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• kaushalmodi (orginal) [2019-11-03T12:13:28+01:00] view original

  If you use countUp in the loop, it will optimize your code a bit as it accepts the step size.

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• hugogranstrom (orginal) [2019-11-03T13:05:03+01:00] view original

  Great! :-) will try it out.

  What I'm trying to do is that I'm starting a DSP (digital signal processing) module for NumericalNim and getting every Nth element is quite useful.

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• kaushalmodi (orginal) [2019-11-03T15:26:27+01:00] view original

  Not exactly what you were looking for, but here's a related fun little snippet: https://play.nim-lang.org/#ix=20Hp

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• hugogranstrom (orginal) [2019-11-03T16:19:02+01:00] view original

  It was interesting ;) I should use iterators more instead of hard to read loops with indices

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