5 kyu

Pick peaks

10,195 of 30,141frenetic_be

Description:

In this kata, you will write a function that returns the positions and the values of the "peaks" (or local maxima) of a numeric array.

For example, the array arr = [0, 1, 2, 5, 1, 0] has a peak at position 3 with a value of 5 (since arr[3] equals 5).

The output will be returned as an object with two properties: pos and peaks. Both of these properties should be arrays. If there is no peak in the given array, then the output should be {pos: [], peaks: []}.

Example: pickPeaks([3, 2, 3, 6, 4, 1, 2, 3, 2, 1, 2, 3]) should return {pos: [3, 7], peaks: [6, 3]} (or equivalent in other languages)

All input arrays will be valid integer arrays (although it could still be empty), so you won't need to validate the input.

The first and last elements of the array will not be considered as peaks (in the context of a mathematical function, we don't know what is after and before and therefore, we don't know if it is a peak or not).

Also, beware of plateaus !!! [1, 2, 2, 2, 1] has a peak while [1, 2, 2, 2, 3] and [1, 2, 2, 2, 2] do not. In case of a plateau-peak, please only return the position and value of the beginning of the plateau. For example: pickPeaks([1, 2, 2, 2, 1]) returns {pos: [1], peaks: [2]} (or equivalent in other languages)

Have fun!

Arrays
Algorithms

Stats:

CreatedNov 6, 2013
PublishedNov 6, 2013
Warriors Trained95339
Total Skips21826
Total Code Submissions247715
Total Times Completed30141
JavaScript Completions10195
Python Completions11473
Ruby Completions671
Go Completions1113
PHP Completions674
C++ Completions2213
Java Completions2877
Haskell Completions219
C# Completions1083
F# Completions44
COBOL Completions9
Total Stars1964
% of votes with a positive feedback rating89% of 2980
Total "Very Satisfied" Votes2409
Total "Somewhat Satisfied" Votes490
Total "Not Satisfied" Votes81
Ad
Contributors
  • frenetic_be Avatar
  • jhoffner Avatar
  • Unnamed Avatar
  • GiacomoSorbi Avatar
  • donaldsebleung Avatar
  • JohanWiltink Avatar
  • JorgeVS Avatar
  • Blind4Basics Avatar
  • pmatseykanets Avatar
  • Voile Avatar
  • neilm Avatar
  • scorphus Avatar
  • KataSideKick Avatar
  • FArekkusu Avatar
  • user9644768 Avatar
  • hobovsky Avatar
  • rge123 Avatar
  • akar-0 Avatar
  • dfhwze Avatar
  • Just4FunCoder Avatar
  • saudiGuy Avatar
Ad