THIS ASSIGNMENT WAS NOT GIVEN ON 2014-2015 SCHOOL YEAR

1. Simulate one step. The step() method simulates one step of the LFSR and returns the rightmost bit as an integer (0 or 1). For example,

// LFSR lfsr1 = new LFSR("01101000010", 9);
// for this assignment the seed and tap can be hardcoded or input
String lfsr1 = "01101000010";
int tap = 9;
StdOut.println(lfsr1);
for (int i = 0; i < 10; i++) {
    // int bit = lfsr1.step();
    // code to create a sequence of 0s and 1s like the example below
    StdOut.println(lfsr1 + " " + bit);
}

outputs
01101000010
11010000101 1
10100001011 1
01000010110 0
10000101100 0
00001011001 1
00010110010 0
00101100100 0
01011001001 1
10110010010 0
01100100100 0

2. Extracting multiple bits. The method generate() takes a positive integer k as an argument and returns a k-bit integer obtained by simulating k steps of the LFSR. This task is easy to accomplish with a little arithmetic:

• initialize a variable to zero
• for each bit extracted, double the variable
• add the bit returned by step()

For example, extracting (from left to right) each bit from the sequence 1 1 0 0 1, the variable takes on the values 1, 3, 6, 12, and 25, ending with the binary representation of the bit sequence.

gen = 0
gen = gen * 2 + new_bit = 0 * 2 + 1 = 1
gen = gen * 2 + new_bit = 1 * 2 + 1 = 3
gen = gen * 2 + new_bit = 3 * 2 + 0 = 6
gen = gen * 2 + new_bit = 6 * 2 + 0 = 12
gen = gen * 2 + new_bit = 12 * 2 + 1 = 25

For example,

// LFSR lfsr2 = new LFSR("01101000010", 9); 
// for this assignment the seed and tap can be hardcoded or input
String lfsr2 = "01101000010";
int tap = 9;
StdOut.println(lfsr2);
for (int i = 0; i < 10; i++) {
    // int r = lfsr2.generate(5);
    // code to generate a number like 25 in the example above
    StdOut.println(lfsr2 + " " + r);
}

outputs
01101000010
00001011001 25
01100100100 4
10010011110 30
01111011011 27
01101110010 18
11001011010 26
01101011100 28
01110011000 24
01100010111 23
01011111101 29

Asignment:
Write a java program, LFSRSim_YI.java to generate an output like the one right above for a given seed.
NOTE: It doesn’t have to be OOP

Animations using java

THIS ASSIGNMENT WAS NOT GIVEN ON 2014-2015 SCHOOL YEAR

/**
 *  Thr Picture.java class provides methods for manipulating individual pixels of
 *  an image. The original image can be read from a .jpg, .gif,
 *  or .png file or the user can create a blank image of a given size.
 *  This class includes methods for displaying the image in a window on
 *  the screen or saving it to a file.
 *

Picture.java (if this file is not the latest version, visit the Standard Library Site)

* Pixel (x, y) is column x and row y. * By default, the origin (0, 0) is upper left, which is a common convention * in image processing. * The method setOriginLowerLeft() change the origin to the lower left. *

* For additional documentation, see * Section 3.1 of * Introduction to Programming in Java: An Interdisciplinary Approach

* by Robert Sedgewick and Kevin Wayne. * * @author Robert Sedgewick * @author Kevin Wayne

More information on processing images is in the link below

Assignment: Write a java program, Pixels30x30_YI.java to display the RGB colors of the top area of the image in this format:

R     G    B
196   200  105
155   0    50
...