Lecture (6)

1. Lecture (6) Programming (3) Eng. Osama Talaat

2. Announcement • Previous lecture videos are available at the course link. • Extra Materials. • Survey.

3. Password • Enter the password. • If the entered password is ‘a13’, display a welcome message ‘Welcome Osama’. • If the entered password is ‘com’, display a welcome message ‘Welcome Hamdy’. • If the entered password is ‘t10’, display a welcome message ‘Welcome Mona’. • Else, Display an error message ‘Wrong password’. • Give the user only 5 unsuccessful trails.

4. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Designed by: Eng. Osama Talaat % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clear all; close all; clc; for k=1:5 pass = input('Please enter password: ','s'); ifstrcmp(pass,'a13') disp('Welcome Osama') break elseifstrcmp(pass,'com') disp('Welcome Hamdy') break elseifstrcmp(pass,'t10') disp('Welcome Mona') break else disp(['Wrong password, trial ' num2str(k) ' of 5']) end end What it wrong ?? Break & Continue Ctrl + C

5. Animation %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Designed by: Eng. Osama Talaat % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clear all; close all; clc; [x,y]=meshgrid(-2:0.1:2); z=x.*exp(-x.^2-y.^2); surf(x,y,z)

6. View • Change the angle of view for a figure. • Get the current angles: >> [a,b]=view a = -37.5000 b = 30

7. Animation %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Designed by: Eng. Osama Talaat % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clear all; close all; clc; [x,y]=meshgrid(-2:0.1:2); z=x.*exp(-x.^2-y.^2); surf(x,y,z) foraz=-37.5:7.5:37.5+360 view(az,30) end

8. Pause • Pause for n seconds: >> pause(n) • Pause till you press any key >> pause

9. Animation %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Designed by: Eng. Osama Talaat % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clear all; close all; clc; [x,y]=meshgrid(-2:0.1:2); z=x.*exp(-x.^2-y.^2); surf(x,y,z) pause(1) foraz=-37.5:7.5:37.5+360 pause(0.2) view(az,30) end

10. For inside for %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Designed by: Eng. Osama Talaat % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clear all; close all; clc; a=randi(30,40,20); c=0; fori=1:size(a,1) for j=1:size(a,2) if(a(i,j)==3) c=c+1; end end end disp('The number of accurance of 3s:'); disp(c)

11. Game • The program generate a random integer number from 0:15. • The user guess that number, if he was wrong the program will till him that his guess is lower or greater than the number. • Then the user try again, till he give the right guess. • The program will display a congratulation message and the number of trials he took.

12. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Designed by: Eng. Osama Talaat % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clear all; close all; clc; n=randi(15); trials=0; g=-1; while(g~=n) g=input('Enter your guess between 1-15: '); if g>n disp('Your guess is greater, try again!') trials=trials+1 elseif g<n disp('Your guess is smaller, try again!') trials=trials+1 else disp('Congratulations, your guess is right!') trials=trials+1 end end

13. While Loop whileconditions ________________________ ______ Commands ________ ________________________ end ________________________ ______ Commands ________ ________________________

14. While & For for x=1:2:100 ________________________ ______ Commands ________ ________________________ end ---------------------------- x=1; whilex<=100 ________________________ ______ Commands ________ ________________________ x=x+2; end

15. 12 1 11 10 2 9 3 8 4 5 7 6 15-Min Break Survey

16. Functions • To run any script (plotsin.m for example): • Run. • F5 • In command window >> plotsin • Create a function: functionplotsin(inputs) ________________________ ______ Commands ________ ________________________ • The file and the functions names must be the same. • The file must be saved in the current directory.

17. Functions functionplotsin(n,f,A) if n>0 %Check positive number of cycles x=[0:0.1:2*pi*n/f]; y=A*sin(f*x); plot(x,y) xlabel('x') ylabel([num2str(A) 'sin(' num2str(f) 'x)']) title('Sine Curve'); grid disp('The amplitude values are: '); disp(y) else disp('The number of cycles must be positive') end disp('Program Terminated !!')

18. Log of any base • Create a function to calculate the log: • Create new script called logn: functionlogn(x,n) log(x)/log(n) • Try in the command editor: >> logn(27,3) ans = 3.0000

19. Log of any base • Try in the command editor: >> a=logn(27,3) Error using logn Too many output arguments. • Create an output for the function: function y=logn(x,n) y=log(x)/log(n); • Check wrong values: function y=logn(x,n) if n<=0 disp('The base must be positive') end y=log(x)/log(n);

20. Log of any base function y=logn(x,n) if n<=0 disp('The base must be positive') return end y=log(x)/log(n); --- OR --- function y=logn(x,n) if n<=0 error('The base must be positive') end y=log(x)/log(n);

21. Insert into a vector function out=insertv(in,new,n) ifsize(in,1)~=1|size(new,1)~=1 error('Works only with vectors') end if n<=0 error('The index must be positive') end out=[in(1:n-1) new in(n:end)];

22. Open Selection • You can open the code of some functions of MATLAB. • You can also change in it and save it for yourself or publish it with some rules. • Type any function in the command window. • Select it. • Right click. • Open Selection. • Its code will appear in the editor where you can view, change and save as ...

23. MATLAB Tips !! • Tic ... Toc %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Designed by: Eng. Osama Talaat % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clear all; close all; clc; disp('Press any key to start the stop watch!') pause tic disp('Press any key to stop!') pause toc

24. Close MATLAB • X button. • Code >> exit >> quit • Ctrl + Q

25. GOOD LUCK To be continued in the next lecture …