MATLAB实验作业一.docx

MATLAB的基本操作(一)实验内容及步骤1. 进入MATLAB工作环境，熟悉各窗口的功能。（1） 双击桌面图标，或从“开始”菜单打开MATLAB.exe,启动MATLAB。（2） 查看MATLAB界面各窗口的布局、了解其功能，并完成各窗口之间的切换。（3） 设置当前工作目录。在D盘创建mymatlab目录，并将其作为当前工作目录。今后的实验过程中以此目录作为当前工作目录。2. 计算5.542+cos3517.893.5-e2的值。（1） 在命令窗口（Command Window）中输入程序：a=5.542+cos(3/5*pi)*sqrt(17.89)/3.5-exp(2)（2） 按回车键运行，如果出现“Error”（出错信息），则应找出原因并改正，再运行。（3） 运行结果22.9291过程： a=5.542+cos(3/5*pi)*sqrt(17.89)/3.5-exp(2)a = 22.92913输入矩阵A=428256319, B=111222333, 在命令窗口中执行下列表达式，掌握其含义： A(2,3) A(:,2) A(3,:) A(:,1:2:3) A(:,3).*B(:,2) A(:,3)*B(2,:) A*B A.*B A2 A.2 B/A B./A （1）在命令窗口键入A=4 2 8;2 5 6;3 1 9 ,生成矩阵A;键入B=1 1 1;2 2 2;3 3 3 ，生成矩阵B。（2）记录执行以下表达式的结果：A(2，3)=6，A(6)=1，A(:,2)=251，A(3，:)=319，A(:,1:2:3)=482639，A(:,3).*B(:,2)=81227，A(:,3)*B(2,:)=161616121212181818，A*B=323232303030323232，A.*B=428410129327，A2=442611636351004120111，A.2=16464425369181，B/A=0.50000.0769-0.38461.00000.1538-0.76921.50000.2308-1.1538, B./A=0.25000.50000.12501.00000.40000.33331.00003.00000.3333,B.A=4.00002.00008.00001.00002.50003.00001.00000.33333.0000过程：A=4 2 8;2 5 6;3 1 9A = 4 2 8 2 5 6 3 1 9 B=1 1 1;2 2 2;3 3 3B = 1 1 1 2 2 2 3 3 3 A(2,3)ans = 6 A(6)ans = 1 A(:,2)ans = 2 5 1 A(3,:)ans = 3 1 9 A(:,1:2:3)ans = 4 8 2 6 3 9 A(:,3).*B(:,2)ans = 8 12 27 A(:,3)*B(2,:)ans = 16 16 16 12 12 12 18 18 18 A*Bans = 32 32 32 30 30 30 32 32 32 A.*Bans = 4 2 8 4 10 12 9 3 27 A2ans = 44 26 116 36 35 100 41 20 111 A.2ans = 16 4 64 4 25 36 9 1 81 B/Aans = 0.5000 0.0769 -0.3846 1.0000 0.1538 -0.7692 1.5000 0.2308 -1.1538 B./Aans = 0.2500 0.5000 0.1250 1.0000 0.4000 0.33331.0 3.0000 0.3333 B.Aans = 4.0000 2.0000 8.0000 1.0000 2.5000 3.0000 1.0000 0.3333 3.00004. 产生一个5阶魔方矩阵，将矩阵的第3行4列元素赋值给变量a；将由矩阵第2,3,4行第2,5列构成的子矩阵赋值给变量b。（1）在命令窗口键入clear和clc，观察命令窗口内容的变化。clear命令的作用是清除MATLAB工作空间中保存的变量。clc命令的作用是清除指令窗中显示内容。（2）利用magic()函数产生魔方矩阵，并将此矩阵赋给变量M。程序 M=magic(5)M = 17 24 1 8 15 23 5 7 14 16 4 6 13 20 22 10 12 19 21 311 18 25 2 9（3）将矩阵M的第3行第4列元素赋值给变量a。程序 a=M(3,4)a =20（4） 将由矩阵M第2,3,4行第2,5列构成的子矩阵赋值给变量b。程序 b=M(2 3 4,2 5)b = 5 16 6 22 12 35.建立如下矩阵。（1）20100020100000 20101010程序: 2010*eye(10)ans = 2010 0 0 0 0 0 0 0 0 00 2010 0 0 0 0 0 0 0 0 0 0 2010 0 0 0 0 0 0 0 0 0 0 2010 0 0 0 0 0 0 0 0 0 0 2010 0 0 0 0 0 0 0 0 0 0 2010 0 0 0 0 0 0 0 0 0 0 2010 0 0 0 0 0 0 0 0 0 0 2010 0 0 0 0 0 0 0 0 0 0 2010 0 0 0 0 0 0 0 0 0 0 2010 (2)06606666 088程序: 6*ones(8)-6*eye(8)ans = 0 6 6 6 6 6 6 6 6 0 6 6 6 6 6 6 6 6 0 6 6 6 6 6 6 6 6 0 6 6 6 6 6 6 6 6 0 6 6 6 6 6 6 6 6 0 6 6 6 6 6 6 6 6 0 6 6 6 6 6 6 6 6 06.设有分块矩阵A=E33R32O23D22,其中E,R,O,D分别为单位矩阵、随机阵、零阵和对角阵e002。（1）生成单位阵E，程序： E=eye(3)E = 1 0 0 0 1 0 0 0 1（2）生成随机阵R，程序： R=rand(3,2)R = 0.9501 0.4860 0.2311 0.8913 0.6068 0.7621（3）生成零阵O，程序： O=zeros(2,3)O = 0 0 0 0 0 0（4）生成对角阵D，程序： D=exp(1) 0;0 2D = 2.7183 0 0 2.0000（5）生成矩阵A，程序： A=E R;O DA = 1.0000 0 0 0.9501 0.4860 0 1.0000 0 0.2311 0.8913 0 0 1.0000 0.6068 0.7621 0 0 0 2.7183 0 0 0 0 0 2.00007.查看polt函数的帮助文档，并查看Demos中关于plot的示例程序。（1）在命令窗口输入help plot,查看plot函数的帮助文档。（2）点击“help”菜单，选择“Demons”子菜单，在“MATLAB”中选择“Graphics”,再选择“2-D Plots”，即可看到关于plot函数的示例程序。过程：（1） help plot PLOT Linear plot. PLOT(X,Y) plots vector Y versus vector X. If X or Y is a matrix, then the vector is plotted versus the rows or columns of the matrix, whichever line up. If X is a scalar and Y is a vector, length(Y) disconnected points are plotted. PLOT(Y) plots the columns of Y versus their index. If Y is complex, PLOT(Y) is equivalent to PLOT(real(Y),imag(Y). In all other uses of PLOT, the imaginary part is ignored. Various line types, plot symbols and colors may be obtained with PLOT(X,Y,S) where S is a character string made from one element from any or all the following 3 columns: b blue . point - solid g green o circle : dotted r red x x-mark -. dashdot c cyan + plus - dashed m magenta * star (none) no line y yellow s square k black d diamond v triangle (down) triangle (up) triangle (right) p pentagram h hexagram For example, PLOT(X,Y,c+:) plots a cyan dotted line with a plus at each data point; PLOT(X,Y,bd) plots blue diamond at each data point but does not draw any line. PLOT(X1,Y1,S1,X2,Y2,S2,X3,Y3,S3,.) combines the plots defined by the (X,Y,S) triples, where the Xs and Ys are vectors or matrices and the Ss are strings. For example, PLOT(X,Y,y-,X,Y,go) plots the data twice, with a solid yellow line interpolating green circles at the data points. The PLOT command, if no color is specified, makes automatic use of the colors specified by the axes ColorOrder property. The default ColorOrder is listed in the table above for color systems where the default is blue for one line, and for multiple lines, to cycle through the first six colors in the table. For monochrome systems, PLOT cycles over the axes LineStyleOrder property. If you do not specify a marker type, PLOT uses no marker. If you do not specify a line style, PLOT uses a solid line. PLOT(AX,.) plots into the axes with handle AX. PLOT returns a column vector of handles to lineseries objects, one handle per plotted line. The X,Y pairs, or X,Y,S triples, can be followed by parameter/value pairs to specify additional properties of the lines. For example, PLOT(X,Y,LineWidth,2,Color,.6 0 0) will create a plot with a dark red line width of 2 points. Backwards compatibility PLOT(v6,.) creates line objects instead of lineseries objects for compatibility with MATLAB 6.5 and earlier. See also plottools, semilogx, semilogy, loglog, plotyy, plot3, grid, title, xlabel, ylabel, axis, axes, hold, legend, subplot, scatter. Overloaded functions or methods (ones with the same name in other directories) help phytree/plot.m help cfit/plot.m help fints/plot.m help idmodel/plot.m help idfrd/plot.m help iddata/plot.m help mpc/plot.m help frd/plot.m help dspdata/plot.