repeating numbers in an array
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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.?
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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?)
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