1.开发环境介绍
是路径文件夹选择.是当前文件夹显示是点击文件夹的某一文件，可以具体显示命令行窗口显示命名行窗口的变量和值本图中被隐藏了，历史代码显示2.变量命名规则
变量名区分大小写变量名长度不超过63位变量名以字母开头，可以由字母，数字，和下划线组成，但不能是标点变量名应简洁明了，通过变量名可以简单看出含义3.数据类型
数字字符与字符串矩阵元胞数组结构体基本操作
%% I. 清空环境变量及命令 clear all % 清除Workspace中的所有变量 clc % 清除Command Window中的所有命令 %% II. 变量命令规则 %% % 1. 变量名区分大小写 A = 2 a = 3 %% % 2. 变量名长度不超过63位 ABCDEFGHIJKLMNOPQRSTUVWXYZ123456ABCDEFGHIJKLMNOPQRSTUVWXYZ123456 = 3 %% % 3. 变量名以字母开头，可以由字母、数字和下划线组成，但不能使用标点 % 3A = 4 % .a = 5 % /b = 5 a_2 = 3 % a.2 = 4 %% % 4. 变量名应简洁明了，通过变量名可以直观看出变量所表示的物理意义 A = rand(3,5) rows = size(A, 1) cols = size(A, 2) %% III. MATLAB数据类型 %% % 1. 数字 2 + 4 10 - 7 3 * 5 8 / 2 %% % 2. 字符与字符串 s = 'a' abs(s) char(65) num2str(65) str = 'I Love MATLAB & Machine Learning.' length(str) doc num2str %% % 3. 矩阵 A = [1 2 3; 4 5 2; 3 2 7] B = A'%转置 C = A(:)%列向量 D = inv(A)%逆 A * D E = zeros(10,5,3) E(:,:,1) = rand(10,5) E(:,:,2) = randi(5, 10,5) E(:,:,3) = randn(10,5) %% % 4. 元胞数组 A = cell(1, 6) A{2} = eye(3) A{5} = magic(5) B = A{5} %% % 5. 结构体 books = struct('name',{{'Machine Learning','Data Mining'}},'price',[30 40]) books.name books.name(1) books.name{1} %% IV. MATLAB矩阵操作 %% % 1. 矩阵的定义与构造 A = [1 2 3 5 8 5 4 6] B = 1:2:9 C = repmat(B, 3, 1)%复制，将B复制成3行1列 D = ones(2, 4) %% % 2. 矩阵的四则运算 A = [1 2 3 4; 5 6 7 8] B = [1 1 2 2; 2 2 1 1] C = A + B D = A - B E = A * B'%矩阵进行计算 F = A .* B具体数值进行计算 G = A / B % G * B = A G * B * pinv(B) = A * pinv(B) G = A * pinv(B) H = A ./ B %% % 3. 矩阵的下标 A = magic(5) B = A(2,3) C = A(3,:) D = A(:,4) [m, n] = find(A > 20) %% V. MATLAB逻辑与流程控制 %% % 1. if ... else ... end A = rand(1,10) limit = 0.75; B = (A > limit); % B is a vector of logical values if any(B) fprintf('Indices of values > %4.2f: \n', limit); disp(find(B))%dis输出 else disp('All values are below the limit.') end %% % 2. for ... end k = 10; hilbert = zeros(k,k); % Preallocate matrix for m = 1:k for n = 1:k hilbert(m,n) = 1/(m+n -1); end end hilbert %% % 3. while ... end n = 1; nFactorial = 1; while nFactorial < 1e100 n = n + 1; nFactorial = nFactorial * n; end n factorial(69) factorial(70) prod(1:69) prod(1:70) %% % 4. switch ... case ... end mynumber = input('Enter a number:'); switch mynumber case -1 disp('negative one'); case 0 disp('zero'); case 1 disp('positive one'); otherwise disp('other value'); end %% VI. MATLAB脚本与函数文件 %% % 1. 脚本文件 myScript %% % 2. 函数文件 mynumber = input('Enter a number:'); output = myFunction(mynumber) %% VII. MATLAB基本绘图操作 %% % 1. 二维平面绘图 x = 0:0.01:2*pi; y = sin(x); figure plot(x, y) title('y = sin(x)') xlabel('x') ylabel('sin(x)') xlim([0 2*pi]) x = 0:0.01:20; y1 = 200*exp(-0.05*x).*sin(x); y2 = 0.8*exp(-0.5*x).*sin(10*x); figure [AX,H1,H2] = plotyy(x,y1,x,y2,'plot');%两个纵坐标 set(get(AX(1),'Ylabel'),'String','Slow Decay') set(get(AX(2),'Ylabel'),'String','Fast Decay') xlabel('Time (\musec)') title('Multiple Decay Rates') set(H1,'LineStyle','--') set(H2,'LineStyle',':') %% % 2. 三维立体绘图 t = 0:pi/50:10*pi; plot3(sin(t),cos(t),t) xlabel('sin(t)') ylabel('cos(t)') zlabel('t') grid on axis square %% % 3. 图形的保存与导出 % (1) Edit → Copy Figure % (2) Toolbar → Save % (3) print('-depsc','-tiff','-r300','picture1') % (4) File → Export Setup %% VIII. MATLAB文件导入 %% % 1. mat格式 save data.mat x y1 y2 clear all load data.mat %% % 2. txt格式 M = importdata('myfile.txt'); S = M.data; save 'data.txt' S -ascii T = load('data.txt'); isequal(S, T) %% % 3. xls格式 xlswrite('data.xls',S) W = xlsread('data.xls'); isequal(S, W) xlswrite('data.xlsx',S) U = xlsread('data.xlsx'); isequal(S, U) %% % 4. csv格式 csvwrite('data.csv',S) V = csvread('data.csv'); isequal(S, V)m函数文件
function output = myFunction(input) switch input case -1 output = 'negative one'; case 0 output = 'zero'; case 1 output = 'positive one'; otherwise output = 'other value'; end end mynumber = input('Enter a number:'); switch mynumber case -1 disp('negative one'); case 0 disp('zero'); case 1 disp('positive one'); otherwise disp('other value'); end作者：电气工程的计算机萌新-余登武
