Hi APLers, first, many thanks to Mohammad, Kacper and Hans-Peter for your hints regarding 2019/02. I learned a lot, and tried to incooperate in my solution for 2019/03, having had a deeper look in ∘.X, outer product!
3: Grade Distribution (https://www.dyalog.com/uploads/files/student_competition/2019_problems_phase1.pdf) "The school's administrative department wants to publish some simple statistics. Given anon-empty character vector of single-letter grades, produce a 3-column, 5-row,alphabetically-sorted matrix of each grade, the number of occurrences of that grade, andthe percentage (rounded to 1 decimal position) of the total number of occurrences ofthat grade. The table should have a row for each grade even if there are no occurrencesof a grade. Note: due to rounding the last column might not total 100%. Hint: The key operator ⌸ could be useful for this problem." (from the exercise) ∇table←gradeDistri grades;allgr allgr←⍪'ABCDF' ⍝ all available grades table←allgr,+/allgr ∘.= ,grades ⍝ outer product =, and sum 1s up table←table,+/table[;2] ⍝ 3rd column with sum table[;3]←10÷⍨⌊0.5+1000×table[;2]÷table[;3] ⍝ calculate col2÷col3 and round ⍝ for sure, rounding could also be done ⍝ with ⍕! ∇ br & many thanks for any hint! - Otto -- Dipl. Ing. (FH) Otto Diesenbacher-Reinmüller diesenbacher.net Salzburg, Österreich
