repeating numbers in an array

i have a problem i have a large array i want to check if there is a repeating number in that array; if yes than detect.?

More Answers (1)

Steven Lord
Steven Lord on 13 Sep 2017
Do you want to detect repeated numbers anywhere in the array (you want to detect both [1 2 2 3 1] and [1 2 3 1 2]) or just repeated numbers adjacent to one another (detect [1 2 2 3 1] but not [1 2 3 1 2])? In the latter case, take a look at the diff function.
In the former case, the unique function would work as KL suggested. Alternately, if your numbers are floating-point values and you want to consider two numbers repeated if they are "close enough" take a look at the uniquetol function. Depending on the exact information you want there may be other approaches that use less memory and/or time.
  • Do you just want to know whether there is or is not a repeated element (existence?)
  • Do you want to know how many repeated elements (count?)
  • Do you want to know where they are (location?)

1 Comment

dear sir. I just want to know if there is any repeating number in the array, no matters how many times?

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on 13 Sep 2017

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on 15 Sep 2017

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