Scale Mutator Program

Scale Mutator Program Array Manipulation

FunNotesSHELL.java • Each scale is an array of integers • Representing pitch for each note in the scale • Write methods to mutate the scales into a more interesting order: • Reversed • Scrambled (randomized) • Shuffled • Sorted • Sequenced (as sets of triads)

Methods to Write • void swap(int[] list, int a, int b) • void selSort(int[] list) selSort describes a Selection Sort. Look them up in the book. We will dig into the details later.

int[] scramble(int[]list) • Given an array of ints called list, return a new array of the same size and data but with the order of the data randomized. • Easy ideas?

int[] scramble(int[]list) • Given an array of ints called list, return a new array of the same size and data but with the order of the data randomized. • Easy ideas? • You have a swap method that will swap the values at two indexes. • Pick two random indexes from the array and swap them. Repeat 10,000 times.

int[] scramble(int[]list) • Given an array of ints called list, return a new array of the same size and data but with the order of the data randomized. • Another idea: • Pick a random element from list that is not -1 • Store that element in the next available index of an answer array • Replace the element in list with -1 • Repeat until the answer array is full

int[] scramble(int[]list) list r ansi

int[] reverse(int[]list) • Given an array of ints called list, return a new array of the same size and data but with the order of the data reversed. • Easy ideas?

int[] reverse(int[]list) • Given an array of ints called list, return a new array of the same size and data but with the order of the data reversed. • Easy ideas? • Traverse through list from the last index to the first, copying each element into increasing indexes of the return array.

int[] makePalindrome(int[]list) • Given an array of ints called list, return a new array almost twice the size with all of the elements in order followed by all the elements in reverse order. • The last element of list should not appear twice. int [] list = {1,2,3,4}; int [] list2 = makePalindrome(list); //list2 should contain 1,2,3,4,3,2,1 Easy ideas?

int[] makePalindrome(int[]list) • Given an array of ints called list, return a new array almost twice the size with all of the elements in order followed by all the elements in reverse order. • The last element of list should not appear twice. int [] list = {1,2,3,4}; int [] list2 = makePalindrome(list); //list2 should contain 1,2,3,4,3,2,1 Easy ideas? You already have a reverse method. Why not use it?

int[] shuffle(int[]list) • Given an array of ints called list, return a new array of the same size, in the order of 1stelem, last element, 2nd element, 2nd to last element, 3rd element, 3rd to last element, etc. int [] list = {1,2,3,4,5,6,7,8}; int [] list2 = shuffle(list); //list2 should contain 1,8,2,7,3,6,4,5 Easy ideas?

int[] shuffle(int[]list) list a b ansi

int[] shuffle(int[]list) list ab ansi

int[] shuffle(int[]a, int[]b) • Given 2 arrays of ints called a and b, return a new array of all the combined elements of a and b, in the order of 1stelem from a, 1st element from b, 2nd element from a , 2nd element from b, 3rd element from a, 3rd element from b, etc. int [] list1 = {1,2,3,4}; int [] list2 = {5,6,7,8}; int [] list3 = shuffle(list1, list2); //list2 should contain 1,5,2,6,3,7,4,8

int[] mixWithNote(int[] list, int note) • Given an array of ints called list, and a single value called note, return a new array of all the elements of list alternating with note: 1stelem from list, note, 2nd element from list, note, 3rd element from list , note, etc. int [] list1 = {1,2,3,4}; int [] list2 = mixWithNote(list1, 9); //list2 should contain 1,9,2,9,3,9,4,9

int[] triads(int[] list) • Given an array of ints called list, return a new array of all the elements of list in groups of 3 consecutive elements: 1stelem from list, 2nd element from list, 3rd element from list , 2nd element from list, 3rd element from list, 4th element from list, 3rd element from list, 4th element from list, 5th element from list, etc. int [] list1 = {1,2,3,4,5,6}; int [] list2 = triads(list1); //list2 should contain 1,2,3,2,3,4,3,4,5,4,5,6 Given list1 is size n, how big should list2 be?

int [] list1 = {1,2,3};//size int [] list2 = triads(list1); //1,2,3: size 3 int [] list1 = {1,2,3,4};//size 4 int [] list2 = triads(list1); //1,2,3,2,3,4: size 6 int [] list1 = {1,2,3,4,5};//size 5 int [] list2 = triads(list1); //1,2,3,2,3,4,3,4,5: size 9 int [] list1 = {1,2,3,4,5,6}; //size 6 int [] list2 = triads(list1);//1,2,3,2,3,4,3,4,5,4,5,6: size 12

int[] triads(int[]list) list a ansi

Scale Mutator Program