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I have a list "d" that looks like this:

d={{{1,4},{1,1},{1,2}},
{{1,4}},{1,1},{3,3}}}

I also have the following code:

For[b = 1, b <= MaxIt, b++, {
  w = Table[
     If[
      d[[b, l]][[1]] == d[[b, l]][[2]],
      Print["Same"],
      Unevaluated@Sequence[]],
     {l, 1, Length[d[[b]]]}];
  }]

List "d" is composed of two generations, each row makes up a single generation. When I run the above loop, I get printed outputs of the word "Same" every time the two numbers in a sublist are the same. The issue is I cannot tell which "Same" refers to which generation. Is there any way to keep my printed words in list form so that they would read {{Same},{Same,Same}}(as in the case above, generation 1 only has 1 same and generation 2 has two sames.

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1 Answer 1

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d = {{{1, 4}, {1, 1}, {1, 2}}, {{1, 4}, {1, 1}, {3, 3}}};

You can Apply the function SameQ at Level 2 to get the result without a loop:

Apply[SameQ, d, {2}]

{{False, True, False}, {False, True, True}}

You can process this list using ReplaceAll to replace False with Nothing and True with "Same":

Apply[SameQ, d, {2}] /. {False -> Nothing, True -> "Same"}

 {{"Same"}, {"Same", "Same"}}
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5
  • $\begingroup$ Thank you for showing me that. I hate to be a bother but is it still possible to do it the way I had done it above? Although I can use the new method you showed me for one part of what I'm doing, I have a section of code that's a little more complicated and is sort of "stuck" in the form similar to what I had shown above. Would you happen to know of a way to do that? $\endgroup$
    – D'Angelo
    Commented Apr 21, 2020 at 6:59
  • $\begingroup$ @D'Angelo, try w = {}; For[b = 1, b <= Length@d, b++, AppendTo[w, Table[If[d[[b, l]][[1]] == d[[b, l]][[2]], "Same", Unevaluated@Sequence[]], {l, 1, Length[d[[b]]]}]]]; w? $\endgroup$
    – kglr
    Commented Apr 21, 2020 at 7:39
  • $\begingroup$ There's an error saying that Part specification 1[[1]] is longer than depth of object $\endgroup$
    – D'Angelo
    Commented Apr 21, 2020 at 8:40
  • $\begingroup$ @D'Angelo, try d = {{{1, 4}, {1, 1}, {1, 2}}, {{1, 4}, {1, 1}, {3, 3}}}; as input (d in your post has a typo.). $\endgroup$
    – kglr
    Commented Apr 21, 2020 at 8:42
  • $\begingroup$ That fixed it, thank you so much $\endgroup$
    – D'Angelo
    Commented Apr 21, 2020 at 8:44

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