Lab 7
CISC 106, Spring 2009
1.(30 points) Write the Selection Sort algorithm first in pseudocode in a text editor (emacs) and save it in
a .txt file called pseudoSelectionSort.txt . Then implement the Selection Sort algorithm in a function
that takes as its input an array of random integers. Call this function selectionSort1.m Use the following
code to generate a 10 element array of random integers.
input = round(rand(1,10)*100);
Call your selection sort algorithm using the 10 element random number array as input. Your function
should print out the unsorted input array you began with and sorted array at the end. Create a diary,
selectionDiary.txt, of you creating the random input from the command window and calling
selectionSort1.m .
2. (30 points) Write a second function called selectionSort2.m . Create a new pseudocode file for this
algorithm called pseudoSelectionSort2.txt . How would you modify your earlier pseudocode to
accommodate the following problem? This function will sort one dimension of a two dimensional array
but will use the second dimension as a tie breaker if elements in the first dimension are equal. Create a
random two dimensional array with the command : -
input = round(rand(2,10)*10);
Call your second selection sort algorithm using the 20 element random number array as input.
Your function should print out the unsorted input array you began with and sorted array at the end.
Create a diary selection2Diary.txt of you creating the random input from the command window and
calling selectionSort2.m
3.Using the MATLAB patch function. The patch command can be used to draw one or more polygons by
defining the coordinates of its vertices. You can use this command to draw shapes on a plot. e.g. goldfish
or a shark.
Type the following into the graphical MATLAB interpreter:
patch([6 7 7 6], [6 6 7 7], 'g')
What do you see? The first array is the x-coordinates and the second array is the y-coordinates. E.g. the
points respectively would be (6,6), (7,6), (7,7), (6,7). These points form a square. What does the ‘g’
mean? What are the bounds of your current plot?
Now type:
