MATLAB programs, for 7th sem CSE students

**Programs coded, compiled and tested by- Tushar kant verma, for CSVTU & CVRU students**

**Semester: VII Branch: Computer Science & Engg.**

**Subject: Soft Computing Lab. Code: 322721 (22)**

**Total Practical Periods:50**

**Total Marks in End Semester Exam: 40**

**1. WRITE MATLAB PROGRAM FOR FOLLOWING.**

A) AREA = π r² (USING ARITHMETIC OPERATOR).

``` Area=pi*r^2 r = 5 Area = 78.5398 ```

B) 5e³ (USING EXPONENTIAL OPERATOR).

>> ``` A=5*exp(3) A = 100.4277 ```

C) y = Sin² π/3 + Cos²π /3 (USING TRIGONOMETRY OPERATOR).

>> ``` y=((sin(pi/3))^2 + (cos(pi/3))^2); disp(y) 1  ```

D) y = Cos π/4 + i Sin π/4 (USING COMPLEX NUMBER).

>> ``` y=(cos(pi/4) + sin(pi/4)*i); disp(y) 0.7071 + 0.7071i ```

E) y= log₁₀(10⁶) (USING LOGARITHMS OPERATOR).

``` y=log10(10^6) y = 6 ```

**2. Compute y- coordinates of a STRAIGHT LINE y = mx + c, where slope of line m =0.5 , intercept c= -2 and x- coordinates : x = 0 to 10 for 0.5 increments.**

``` % A script file to print y-coordinates of straight line. m = 0.5; c = -2; disp(‘Y- Co-ordinates are’); for x=0: 0.5: 10 y = m*x + c; disp(y); disp(‘, ‘); end ```

**Output**: >> straightline Y- Co-ordinates are -2, -1.7500, -1.5000, -1.2500, -1, -0.7500, -0.5000, -0.2500, 0, 0.2500, 0.5000, 0.7500, 1, 1.2500, 1.5000, 1.7500, 2, 2.2500, 2.5000, 2.7500, 3

**3. Create following vectors t with 10 elements 1 to 10.**

**a) x = t sin(t) \[ A MULTIPLY VECTORS\]**

``` disp('Multiple Vectors are'); t = 1: 1: 10; r = sin(t); x = r .* t; disp(x); ```

**Output:**

Multiple Vectors are

0.8415 1.8186 0.4234 -3.0272 -4.7946 -1.6765 4.5989 7.9149 3.7091 -5.4402

**b) y = (t-1) / (t+1) \[ A DIVIDE VECTORS\]**

``` disp(‘Divide Vectors are’); t = 1: 1: 10; y = (t-1) ./ (t+1); disp(y); ```

**Output: **Divide Vectors are

0 0.3333 0.5000 0.6000 0.6667 0.7143 0.7500 0.7778 0.8000 0.8182

**c) z = \[sin(t²)/ (t²)\] \[ A EXPONENTIAL VECTORS\]**

``` disp('EXPONENTIAL VECTORS'); t = 1: 1: 10; z = [ sin(t.^2) ./ (t.^2) ]; disp(z) ```

**Output:**

EXPONENTIAL VECTORS

0.8415 -0.1892 0.0458 -0.0180 -0.0053 -0.0275 -0.0195 0.0144 -0.0078 -0.0051

**4. PLOT y = Sin x where 0 <= x <= 6.5.**

``` x = 0: 0.25: 6.5; y = sin(x); plot(x,y); ```

**Output:**

****

**5. PLOT y = e^-0.4x Sin x where 0 <= x <= 10.**

``` x = 0: .25: 10; y = (exp(-0.4.*x)).*(sin(x)); plot(x,y) ```

**Output:**

****

** **

**6. Write a script file to draw a unit circle.**

``` % Circle - A script file to draw a unit circle theta = linspace(0,2*pi,101); % create a vector theta x = cos(theta); % x-coordinates of circle y = sin(theta); % y-coordinates of circle plot(x,y); % plot the circle axis('equal'); % set x and y scales equal title('Circle of unit radius'); % set graph title ```

**Output:**

>> prgcircle


**7. Write a function factorial to compute the factorial n! for any integer n.**

``` n=input('Enter the number now '); fact = 1; for c=1: 1: n fact = fact * c; end disp(fact); ```

**Output:**

Enter the number now 5

120

**8. Write a function factorial to compute the factorial n! using RECURSION for any integer n.**

``` function y = fact(n) % We have the highest number y = n; % We go down to 0 if n == 0 y = 1; else % We multiply by all the integers before ours, % one at a time... y = y * fact(n-1); end ```

**9. Write a function file crossprod to compute the cross product of two vectors u and v.**

``` function w = crossprod(u,v) % We're assuming that both u and v are 3D vectors. % Naturally, w = [w(1) w(2) w(3)] w(1) = u(2)*v(3) - u(3)*v(2); w(2) = u(3)*v(1) - u(1)*v(3); w(3) = u(1)*v(2) - u(2)*v(1); % Clear screen, clear previous variables and closes all figures clc; close all; clear % Supress empty lines in the output format compact % Define unit vectors i = [1 0 0]; j = [0 1 0]; k = [0 0 1]; % Call the previously created function w1 = crossprod(i,j) w2 = crossprod(i,k) ``` **Output:**w1 = 0 0 1 w2 = 0 -1 0

**10. Write a function to compute the geometric series**

**1 + r + r2 + r3 + ………+ rn for given r and n.**

``` function w = geocomp(r,n); sum = 0; for i=0: 1: n sum = sum + ( i * r ); end sum = sum+1; ```

Note: To run script, do as follows:

Write and save the file under the name ‘**Program\_Name.m**‘.

Now go back to the MATLAB **command window** and type the following command to execute the script file. >>Program\_Name