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I have a long (approx. 4000 rows) list whose elements are in the form as follows:

{{x,y,z},a,b,c}

I want to count the number of elements c in the last column that are greater than a certain number d. How can I do it?

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  • 3
    $\begingroup$ Total@UnitStep[data[[All, -1]] - d]? Of course, Count is much nicer to read, but also much slower. To have something nice to read and fast, check out BoolEval (BoolCount) $\endgroup$ – Szabolcs Sep 21 '18 at 14:29
  • $\begingroup$ The direct route: Count[ data, { __, c_ /; c > d}] $\endgroup$ – Jason B. Sep 21 '18 at 14:32
  • $\begingroup$ Cannot understand what the structure of your list is. $\endgroup$ – Αλέξανδρος Ζεγγ Sep 21 '18 at 14:42
  • $\begingroup$ @ΑλέξανδροςΖεγγ It contains a list and three numbers for each row. $\endgroup$ – mattiav27 Sep 21 '18 at 14:54
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Suppose your long list is named data, one approach can be

Select[data, Last[#] > d &] // Length

where d should have a preset value.

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