(整理)应用MATLAB图形函数和绘图实例.

1、精品文档应用MATLAB图形函数和绘图实例例1. 输入MATLAB程序如下：x = 0 : 0.2 : 12;y1 = Bessel (1, x );y2 = Bessel ( 2, x );y3 = Bessel ( 3, x );figure ( 1 )subplot ( 2, 2, 1 )h = plot ( x, y1, x, y2, x, y3 );set ( h, LineWidth , 2, LineStyle, -; : , -. ) set ( h, Color , R; G ; B )axis ( 0 12-0.5 1)grid onxlabel ( Time )ylabe

2、l ( Amplitude )legend ( h, First, Second , Third )title ( Bessel Functions)y, ix = min (y1 );text ( x ( ix ), y, First Min rightarrow , HorizontalAlignment , right)Print - depsc -tiff -r200 myplot精品文档应用图形编辑模式 如图所示。按此按钮开始图形编辑模式按这些钮开始增 加字符箭头和线File Edit ViWindow Help改变一个轴的3D视角同学们自己练习各项功能。例2.输入MATLAB程序如

3、下:t = 0 : pi/100 : 2*pi;y = sin (t )；Plot ( t, y )grid on继续输入程序如下：y2 = sin (t 0.25 );y3 = sin (t - 0.5 );plot ( t, y, t, y2, t, y3 )可以对线的类型进行定义：t = 0 : pi/100 : 2*pi;y = sin (t )；y2 = sin (t 0.25 );y3 = sin (t - 0.5 );plot ( t, y, -, t, y2, -, t, y3,:)练习，对红的颜色进行编辑。例3. 只绘数据点。输入 MATLAB程序如下:x = 0 : pi

4、/ 15 : 4*pi;y = exp ( 2*cos ( x );plot ( x, y, r+ )+,+ ,+101214进一步对图形进行设置:x = 0 : pi /15 : 4*pi;y = exp ( 2*cos ( x );plot ( x, y, -r , x, y, ok )继续对线类型进行设置：x = 0 : pi / 15 : 4*pi;y1 = exp ( 2*cos ( x );y2 = exp ( 2*sin ( x );plot ( x, y1, -*k , x, y2, -.ok )a 5 ID 15202530354045 5D- 4- 6- a练习：把这两条曲

5、线高成不同颜色。例4. 矩阵的线绘。z = peaks; %矩阵为 49M49 Plot ( z )io86420变换方向来绘图：y = 1 : length ( peaks );plot ( peaks, y )2350壮403530251510例5. 用双Y轴绘曲线。t = 0 : pi/20 : 2*pi;y = exp ( sin (t ); plotyy ( t, y, t, y , plot, stem)i亩2.52.50.50.541001 200 2 欧5由000 5 TW初口900把线性轴和对数轴合并绘图。t = 0 : 900; A = 1000; a = 0.005; b

6、 = 0.005;z1 = A * exp ( -a * t );z2 = sin ( b * t );haxes, hlinel, hline2 = plotyy ( t, z1, t, z2, Semilogy, plot);axes ( haxes ( 1 )ylabel ( Semilog Plot)axes ( haxes ( 2 )ylabel ( Linear Plot)set (hline2, LineStyle,-)o一IX不(Dun例6.轴的限制和标记。命令为： axis ( xmin, xmax, ymin, ymax )。 专用标记和标记标号：x = -pi : .1

7、: pi;y = sin (x );plot ( x, y )set ( gca, XTick , -pi : pi/2 : pi )set ( gca, XTickLabel , -pi, -pi/2, 0, pi/2, pi)xlabel ( - pi leg Theta leg pi)ylabel ( sin ( Theta )title ( plot of sin ( Theta )text ( -pi/4, sin ( -pi/4 ), leftarrow sin (-pidiv4 ), HorizontalAlignment , left) set ( findobj ( gca,

8、 Type, line, Color0 0 1 , Color0.5 0 0.5 , Linewidth 2 )plot of sin ( ) l0.6口 E 0.4 0.2 0-0.2 -D.4 -Q.6 -D.6 - I.pi-pi/20pi/2pi- pi Meg Whetm leg pi例7.绘椭圆。t = 0 : pi/20 : 2*pi;plot ( sin ( t ), 2*cos ( t ) grid on当再加入命令axis square后，绘出图形为如果所加入命令 axis equal后，绘出图形为如果所加入命令axis equal tight后，绘出图形为21.6 050

9、0.6-1-1.5,十 t-1维 i 占I a a, * - d1 一-!7.L.& * 例8.显示多个图形。t = 0 : pi/20 : 2*pi;x, y = meshgrid ( t );subplot ( 2, 2, 1 )plot ( sin ( t ), cos ( t ) axis equal subplot ( 2, 2, 2 )z = sin (x ) + cos ( y );plot ( t, z )axis ( 0 2*pi -2 2 )subplot ( 2, 2, 3 )z = sin ( x ).*cos ( y );plot ( t, z )axis ( 0 2

10、*pi -1 1 )subplot ( 2, 2, 4 )z = ( sin ( x ).A2 ) -( cos ( y ).A2);plot ( t, z )axis ( 0 2*pi -1 1 )1(-17-12例9.计算标注文字的位置。t = 0 : 900;hold on;plot ( t, 0.25 * exp ( -0.005 * t );text ( 300, .25 * exp (- 0.005 * 300 ), bulletleftarrow fontname times 0.25 ite 人-0.005 itt at t = 300 ,F ontSize hold off

11、;例10.更详细标注信息。x = linspace ( 0, 2 * pi, 60 );a = sin ( x );b = cos ( x );hold onstem_handles = stem ( x, a + b );plot_handles = plot ( x, a, , x, b, -g，);xlabel ( Time in musecs )ylabel ( Magnitude )title ( Linear Combination of Two Functions ) legend_handles = stem_handles ; plot_handles ;legend ( l

12、egend_handles, a + b, a = sin ( x ), b = cos ( x )Linear Combinatiori of Twd FunctionsC a + ba = sin ( n )b = cos k )例11.更为复杂的标注说明，包括不同统计量。x = 0:.2:12;plot(x,bessel(1,x),x,bessel(2,x),x,bessel(3,x);legend(First,Second,Third);legend(First,Second,Third,-1)b = bar(rand(10,5),stacked); colormap(summer);

13、 hold onx = plot(1:10,5*rand(10,1),marker,square,markersize,12， markeredgecolor,y,markerfacecolor,.6 0 .6, linestyle,-,color,r,linewidth,2); hold offlegend(b,x,Carrots,Peas,Peppers,Green Beans,.Cucumbers,Eggplant) x = 0:.2:12;plot(x,bessel(1,x),x,bessel(2,x),x,bessel(3,x);legend(First,Second,Third);

14、legend(First,Second,Third,-1)b = bar(rand(10,5),stacked); colormap(summer); hold onx = plot(1:10,5*rand(10,1),marker,square,markersize,12， markeredgecolor,y,markerfacecolor,.6 0 .6,. linestyle,-,color,r,linewidth,2); hold offlegend(b,x,Carrots,Peas,Peppers,Green Beans,.Cucumbers,Eggplant)123456799 1

15、D4.543.532521.510 5D离散数据图形例1.二维的茎图。用函数 y=eYtcosPt。1）连续图形 alpha = .02; beta = .5; t = 0 : 4 : 200 y = exp ( -alpha*t ).*sin ( beta*t ); Plot ( t, y )2)二维的茎图函数为stem ( t, y ),个体具体如下:alpha = .02; beta = .5; t = 0 : 4 : 200 ;y = exp ( -alpha*t ).*sin ( beta*t );stem ( t, y )xlabel ( Time in musecs )ylabe

16、l ( Magnitude )O.B ?0Q-G- T 例11.在Contour绘制的图上标记数值。z = peaks;C , h = contour ( z ,10 );clabel ( C , h )title ( Contour Labeled Using, clabel ( C , h )，) uuFiLuur ilmuhiuu ysiriy*31 C h j45 JO353025201510 55101520253035 4Q 延例12.填充的Contour绘的图z = peaks ;C , h = contourf ( z ,10 );caxis ( -20 20 )title (

17、 Filled Contour Plot Using , Contourf ( z ,10 ) )mitiu uuniuuii liul uing例13.以极坐标形式显示 Contour函数绘图。th , r = meshgrid ( ( 0 : 5 :360 ) * pi/180,0 : .05 :1 );X , Y = pol2cart ( th , r );Z = X + i * Y;f = ( Z .A 4 -1 ) .A ( 1 / 4 );surf (X , Y , abs ( f )hold onsurf ( X , Y , zeros ( size ( X )hold offx

18、label ( Real )ylabel ( Imaginary )zlabel ( Abs ( f )例14.在迪卡尔坐标系中的Contour图。th , r = meshgrid ( ( 0 : 5 :360 ) * pi/180,0 : .05 :1 );X , Y = pol2cart ( th , r );Z = X + i * Y; f = ( Z .人 4-1 ) .A ( 1 / 4 );contour ( X , Y , abs ( f ) , 30 )axis ( -1 1 1 1 )xlabel ( Real , FontSize , 14 )ylabel ( Imagi

19、nary , FontSize, 14 )06060402002-0 4Q60 日-OR -0 4 -0.200.204 口 G 00Real例15.在极轴坐标系中的Contour图。th , r = meshgrid ( ( 0 : 5 :360 ) * pi/180,0 : .05 :1 );X , Y = pol2cart ( th , r );h = polar ( 0 2*pi , 0 1 )delete (h )Z = X + i * Y; f = ( Z .a 4 T ) .a ( 1 / 4 );hold oncontour ( X , Y , abs ( f ) , 30 )

20、270交互式绘图例1.从屏幕上选择绘图的点。axis ( 0 10 0 10 ) hold on xy =;n = 0 ;disp ( Left mouse button picks points .)disp ( Right mouse button picks last points .) but = 1 ;while but = 1xi , yi , but = ginput ( 1 ); plot ( xi , yi , ro ) n= n + 1 ;xy ( :, n ) = xi ; yi ; end t = 1 : n ;ts = 1 : 0.1 :n ;xys = spline

21、 ( t , xy , ts );plot ( xys ( 1，： ) , xys ( 2，： ) , b-) hold offIiiL iIIIi012345679910例2.创建和运行一个 Movie ,图象为最后结果。for k =1 : 16plot ( fft ( eye ( k + 16 )axis equalM ( k ) = getframe ; end movie ( M , 30 )1D.BD.B0.40.20-Q.2-D.JD.E0.0-18-30 丫例3.擦除模式动画。Ay a Ay,其中 A(y)=0-1010dty(2)28-1A = -8/3 0 0 ; 0 T0 10 ; 0 28 T ;y = 35 T0 十;0 0 0 ; 0 0 0 ; h = 0.01 ;p = plot3 ( y ( 1 ) , y ( 2 ) , y ( 3 ) , Square,，EraseMode, background, MarkerSize, 10 ,，MarkerEdgeColor , 1 .7 .7 , MarkerFaceColor , 1 .7 .7 );axis ( 0 50 N5 25 W5