COMP MATLAB.

Transcription

1 COMP1131 MATLAB

2 1

3 2

4 (x, y ) [(x 1,y 1 ) (x 2,y 2 ) (x n,y n )] Y=f(X) X [x 1,x 2,...,x n ] Y [y 1,y 2,,y n ] 3

5 MATLAB 4

6 figure figure figure(n): n figure(n) 5

7 y = x + sin x (x [ π 2, π 2 ]) x=-pi/2:.1:pi/2; y=x+sin(x); figure; plot(x, y);

8 plot (1) plot plot(x,y) x y (x j,y j ) x=:.1:2*pi; y=sin(x); figure; plot(x, y)

9 plot (2) plot plot(y) y 1:n y j n y y=[ ] figure; plot(y);

10 plot (3) plot plot(z) z (real(z j ),image(z j )) z=[1+i,, -1+i]; figure; plot(z);

11 (3, 9) (1, 1) (2, 4) x=[1 2 3] y=x.*x; figure; plot(x, y) 1

12 plot 11

13 (axis) 12

14 Y y axis label 12 1 Light Intensity as a Function of Distance Theory Experiment 8 INTENSITY (lux) 6 4 Comparison between theory and experiment. Data symbol DISTANCE (cm) X x axis label Tick-mark label 13

15 grid on grid off

16 title MATLAB Example title('text'): text >> title('matlab Example')

17 text MATLAB Example MATLAB123 text(x, y, 'content') (x,y) content >> text(,.5, 'MATLAB123') 16

18 text arg ^{arg} 'x^5+6' x 5 +6 _{arg} 'x_1+x_2+x_5' x 1 +x 2 +x 5 \alpha α \pi π \beta β \lambda λ \geq \neg \rightarrow è \leq \times \copyright p171 17

19 text A sin(:) x = :pi/2:2*pi; y = sin(x); plot(x,y) text(pi,,'\leftarrow sin(\pi)')

20 xlabel/ylabel Degree Temperature o xlabel( text ): x text x o ylabel( text ): y text y Date x=[ ]; y=[ ]; figure; plot(x, y); title('temperature', 'FontSize', 16); xlabel('date', 'FontSize', 16); ylabel('degree', 'FontSize', 16); 19

21 (legend) legend(str1, str2,, pos) legend(str1, str2,, 'Location', 'pos') North NorthWest NorthOutside NorthEastOut side Best legend off 2

22 g : m none b c. w o o r * k + + y square x x diamond p172 green magenta blue cyan white red black yellow 21

23 legend 1.8 sin(x) cos(x) x = -pi:pi/2:pi; y1 = sin(x); y2 = cos(x); plot(x,y1,'-ro',x,y2,'-.b') legend('sin(x)','cos(x)')

24 hold on hold off hold hold on hold off 23

25 / sin(x) cos(x) x = -pi:pi/2:pi; y=sin(x); z=cos(x); figure; plot(x, y, '-ob'); hold on; plot(x, z, '--*r'); legend('sin(x)', 'cos(x)', );

26 axis auto axis on axis off axis([xmin,xmax,ymin, ymax]) axis ij axis xy x y [xmin, xmax] [ymin, ymax] 25

27 sin(x) cos(x) x = -pi:pi/2:pi; y=sin(x); z=cos(x); figure; plot(x, y, '-ob'); hold on; plot(x, z, '--*r'); axis([ ]); legend('sin(x)', 'cos(x)', ); x [-2, 2] y [-1, 1] 26

28 Red Green Blue /3 1 RGB R G B 27

29 hsv hot cool pink gray hsv(m) M*3 R/G/B p173 28

30 subplot(m, n, k) m*n k subplot clf 29

31 1 First subplot 1 Second subplot x = linspace(-5,5); y1 = sin(x); subplot(2,2,1) plot(x,y1) title('first subplot') y2 = sin(2*x); subplot(2,2,2) plot(x,y2) title('second subplot') y3 = sin(4*x); subplot(2,2,3) plot(x,y3) title('third subplot') 1.5 Third subplot 1.5 Fourth subplot y4 = sin(6*x); subplot(2,2,4) plot(x,y4) title('fourth subplot')

32 plotyy(x1, Y1, X2, Y2) X1-Y1 X2-Y x = :.1:2; y1 = 2*exp(-.5*x).*sin(x); y2 =.8*exp(-.5*x).*sin(1*x); figure; plotyy(x,y1,x,y2) 31

33 semilogx 7 semilogx x x = :1; y = log(x); figure semilogx(x,y) 32

34 semilogy 1 5 semilogy y x = :.1:1; y = exp(x); figure semilogy(x,y) 33

35 loglog loglog x y x = logspace(-1,2); y = exp(x); figure loglog(x,y,'-s') grid on y=logspace(a, b) y 1 a 1 b 5 34

36 bar hist pie scatter errorbar 35

37 bar 25 bar(y): y y=[ ]; bar(y) bar bar,bar3,barh bar3h Ø bar bar3 Ø barh bar3h 36

38 bar 25 bar(x, y): x y x x=[ ]; y=[ ]; bar(x, y)

39 bar bar(x, y, width): x y x width x=[ ]; y=[ ]; bar(x, y,.2) 38

40 bar overlay bar FaceColor EdgeColor x = [ ]; temp_high = [ ]; w1 =.5; bar(x,temp_high,w1,'facecolor',[.2.2.5], 'EdgeColor', [1 1]) temp_low = [ ]; w2 =.25; hold on bar(x,temp_low,w2,'facecolor',[.7.7]) 39

41 bar ( ) ibt Score Name R L S W A (11) B (12) C (13) bar(x, y): y bar x = [ ]; y = [ ; ; ]; figure; bar(x, y) 4

42 bar ( ) 12 ibt l (bar) l ( ) x = [ ]; y = [ ; ; ]; figure; bar(x, y, 'stacked') 41

43 pie 11% 22% pie(x): x 33% X = [ ]; figure; pie(x) 28% 6% 42

44 pie 22% pie3(x): x 11% 33% 6% 28% X = [ ]; figure; pie3(x) colormap(gray) 43

45 pie 11% 22% pie(x, explode): explode x 33% 6% 28% X = [ ]; figure; explode = [ 1 1 ]; pie(x, explode) 44

46 pie Female pie(, labels): labels X = [5 2]; figure; pie(x, {'Male', 'Female'}) Male 45

47 hist hist x=[ ]; figure; hist(x)

48 hist x = randn(1,1); nbins = 5; hist(x,nbins) randn(n) n*n 47

49 scatter 1.8 scatter x = -pi:pi/2:pi; y=sin(x); figure; scatter(x, y);

50 scatter x = -pi:pi/2:pi; y=sin(x); figure; scatter(x, y, 'MarkerEdgeColor',[1 ], 'LineWidth', 3); 49

51 errorbar errorbar(y, E) 1:n Y j (n Y ) E j j Y j 2E j errorbar(x,y,e) X Y E X Y E x = :pi/1:pi; y = sin(x); e = std(y)*ones(size(x));.4.2 figure errorbar(x,y,e)

52 set set(h, 'PropertyName', PropertyValue) H PropertyName PropertyValue gcf figure gca axes set(gcf, 'Color', 'r') : figure set(gca, 'XTick', [1 5 1]): figure x p581 51

53 XTickLabel WED THU FRI SAT SUN WED THU FRI SAT SUN x=[ ]; y=[ ]; gca bar(x, y) ax = gca; set(ax,'xticklabel',{'wed', 'THU', 'FRI', 'SAT', 'SUN'}) ax.xticklabelrotation = 45; % starting from R214b 52

54 Desktop/Mobile Traffic 6 5 Percentage / 1 Mobile Desktop Mar13 May13 Jul13 Sep13 Nov13 Jan14 Mar14 May14 Time mobile=[ ]; desktop=1-mobile; plot(1:8, mobile, '-+r', 'LineWidth', 2); hold on; plot(1:8, desktop, ':ob', 'LineWidth', 2); ylabel('percentage', 'FontSize', 16); xlabel('time', 'FontSize', 16); axis([1 8 65]); title('desktop/mobile Traffic', 'FontSize', 16); l=legend('mobile', 'Desktop', 'Location', 'SouthEast'); set(l, 'FontSize', 16); set(gca,'xticklabel',{'mar13', 'May13', 'Jul13', 'Sep13', 'Nov13', 'Jan14', 'Mar14', 'May14'}) 53

55 12 Results of ibt (Apr. 216) 1 Total Points Reading Listening Speaking Writing Student ID x = [ ]; y = [ ; ; ]; figure; bar(x, y, 'stacked') l=legend('reading', 'Listening', 'Speaking', 'Writing', 'Location', 'EastOutSide') set(l, 'FontSize', 16) xlabel('student ID', 'FontSize', 16); ylabel('total Points', 'FontSize', 16); title('results of ibt (Apr. 216)', 'FontSize', 16); 54

56 55

57 plot3(x, Y, Z) X Y Z X Y Z x y z X Y Z X Y Z x y z plot3(x1, Y1, Z1, X2, Y2, Z2) X1 Y1 Z1 X2 Y2 Z2 x y z 56

58 t = :pi/5:1*pi; st = sin(t); ct = cos(t); figure plot3(st,ct,t)

59 t = :pi/5:1*pi; st = sin(t); ct = cos(t); ct2 = 1 - cos(t); figure plot3(st,ct,t,st,ct2,t) 58

60 meshgrid meshgrid x=x1:dx:x2; y=y1:dy:y2 [X, Y]=meshgrid(x, y) >> [X,Y] = meshgrid(1:3,1:14) X = Y =

61 mesh(x, Y, Z): X x Y y a=-5:5; b=-5:5; [X, Y]=meshgrid(a, b); Z=2-X.^2-Y.^2; figure; mesh(x, Y, Z); 6

62 mesh surf a=-5:5; b=-5:5; 5 [X, Y]=meshgrid(a, b); -5-5 Z=2-X.^2-Y.^2; figure; surf(x, Y, Z); 61

63 MATLAB Plot Gallery 62