container/numeric_sequence.fz
# This file is part of the Fuzion language implementation. # # The Fuzion language implementation is free software: you can redistribute it # and/or modify it under the terms of the GNU General Public License as published # by the Free Software Foundation, version 3 of the License. # # The Fuzion language implementation is distributed in the hope that it will be # useful, but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public # License for more details. # # You should have received a copy of the GNU General Public License along with The # Fuzion language implementation. If not, see <https://www.gnu.org/licenses/>. # ----------------------------------------------------------------------- # # Tokiwa Software GmbH, Germany # # Source code of Fuzion standard library feature numeric_sequence # # Author: Michael Lill (michael.lill@tokiwa.software) # # ----------------------------------------------------------------------- # numeric_sequence -- a Sequence whose elements inherit from numeric # public numeric_sequence(public N type : numeric, redef from Sequence N ) : searchable_sequence N from, property.equatable is # the arithmetic mean of the sequence # https://en.wikipedia.org/wiki/Arithmetic_mean public average option N => if is_empty nil else cnt := (map N (_ -> N.one)).fold N.sum sum := fold N.sum sum / cnt # the variance of the sequence # https://en.wikipedia.org/wiki/Variance public variance option N => match average nil => nil avg N => cnt := (map N (_ -> N.one )).fold N.sum sum := (map N (x -> (x - avg)**N.two)).fold N.sum sum / cnt # minimum value in the sequence public min option N => if is_empty nil else reduce first ((r,t) -> if r ≤ t then r else t) # maximum value in the sequence public max option N => if is_empty nil else reduce first ((r,t) -> if r ≤ t then t else r) # the median of the sequence # https://en.wikipedia.org/wiki/Median public median option N => if is_empty nil else arr := sorted_array_of numeric_sequence.this if arr.length % 2 = 1 arr[arr.length / 2] else (arr[(arr.length / 2) - 1] + arr[(arr.length / 2)]) / (N.two) # equality check implementation for inherited property.equatable # public fixed type.equality(a, b container.numeric_sequence N) bool => aa := a.as_array ba := b.as_array aa.count = ba.count && ((0..(a.count - 1)) ∀ (i -> aa[i] = ba[i]))