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emacsorg-modeorg-table

Conditionally counting elements in a column in an org-mode spreadsheet

I'm using emacs-calc through org-mode spreadsheet and I would like to count the number of values, in a column, that are greater than a specific value (say 10).

I'm currently using emacs-calc for the computations, but if there is a solution in emacs-lisp, it would be very welcome!

I know that vcount would count the number of values in a vector, but that would count all the values in that vector. How could I add a condition so that only values > 10 are counted?

In other words, I would like a mysterious_function that would return 2 in such a case:

mysterious_function([2,14,11,3,9,1])
Solution

  • I found a solution, using emacs-calc, inspired by choroba's proposal.

    vcount(map(<if(gt(#1,10), 1, [])>, [15,2,5,13]))

    So, for treating a column in org-mode spreadsheet, I can do, for example:

    vcount(map(<if(gt(#1,10), 1, [])>, @I..@II))

    The map function is used to apply a function (an anonymous one, in that case) to each element of a vector. If the element is greater than 10, we put a 1, otherwise an empty vector.