1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
function s=strvcat(varargin)
%   https://ww2.mathworks.cn/help/matlab/ref/strvcat.html
%STRVCAT Vertically concatenate character vectors or string scalars.
%   S = STRVCAT(T1,T2,T3,..) forms the character matrix S containing the
%   text T1,T2,T3,... as rows.  Automatically pads each input
%   with spaces in order to form a valid matrix. Each text parameter, Ti,
%   can itself be a character matrix.  This allows the creation of
%   arbitrarily large character arrays.  Empty character arrays or strings
%   in the input are ignored.
%   形成字符矩阵S，T1,T2,T3，… 按行排列
%   每一行的长度一样，不足的用空格自动填充
%   Ti可以是字符矩阵
%   输入中的空字符数组或字符串将被忽略

%   S = STRVCAT(T), when T is a string array or cell array of character vectors, 
%   each element of T is passed as an input to STRVCAT.  Empty character vectors in
%   the input are ignored.
%   当 T 为字符向量元胞数组时，S = strvcat(T) 将 c 的每个元素作为输入传递给 strvcat
%   输入中的空字符向量将被忽略

%   STRVCAT('Hello','Yes') is the same as ['Hello';'Yes  '] except
%   that the padding is done automatically.
%
%   STRVCAT is not recommended. Use CHAR instead.
%
%   See also STRING, PAD, CHAR, STRCAT

%   Copyright 1984-2016 The MathWorks, Inc.

[varargin{:}] = convertStringsToChars(varargin{:});%将字符串数组转换为字符数组，其他数组不变
%convertStringsToChars，https://ww2.mathworks.cn/help/matlab/ref/convertstringstochars.html

numinput = nargin;
if numinput == 1 && iscellstr(varargin{1}) %iscellstr，确定输入是否为字符向量元胞数组
  varargin = (varargin{1});
end
% find the empty cells 
notempty = ~cellfun('isempty',varargin);
% vertically concatenate the non-empty cells.
s = char(varargin{notempty});

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
function [v1,v2,varargout] = ind2sub(siz,ndx)
%IND2SUB Multiple subscripts from linear index.
%   IND2SUB is used to determine the equivalent subscript values
%   corresponding to a given single index into an array.
%   把矩阵中某个元素的索引值转换为下标

%   [I,J] = IND2SUB(SIZ,IND) returns the arrays I and J containing the
%   equivalent row and column subscripts corresponding to the index
%   matrix IND for a matrix of size SIZ.  
%   For matrices, [I,J] = IND2SUB(SIZE(A),FIND(A>5)) returns the same
%   values as [I,J] = FIND(A>5).
%
%   [I1,I2,I3,...,In] = IND2SUB(SIZ,IND) returns N subscript arrays
%   I1,I2,..,In containing the equivalent N-D array subscripts
%   equivalent to IND for an array of size SIZ.
%
%   Class support for input IND:
%      float: double, single
%      integer: uint8, int8, uint16, int16, uint32, int32, uint64, int64
%
%   See also SUB2IND, FIND.
 
%   Copyright 1984-2015 The MathWorks, Inc. 

nout = max(nargout,1);
siz = double(siz);
lensiz = length(siz);

if lensiz < nout
    siz = [siz ones(1,nout-lensiz)];
elseif lensiz > nout
    siz = [siz(1:nout-1) prod(siz(nout:end))];
end

if nout > 2
    k = cumprod(siz);
    for i = nout:-1:3,
        vi = rem(ndx-1, k(i-1)) + 1;
        vj = (ndx - vi)/k(i-1) + 1;
        varargout{i-2} = double(vj);
        ndx = vi;
    end
end

if nout >= 2
    vi = rem(ndx-1, siz(1)) + 1;
    v2 = double((ndx - vi)/siz(1) + 1);
    v1 = double(vi);
else 
    v1 = double(ndx);
end

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
function b = squeeze(a)
%SQUEEZE Remove singleton dimensions.
%   B = SQUEEZE(A) returns an array B with the same elements as
%   A but with all the singleton dimensions removed.  A singleton
%   is a dimension such that size(A,dim)==1.  2-D arrays are
%   unaffected by squeeze so that row vectors remain rows.
%   返回一个数组，其元素与输入数组 A 相同，但删除了长度为 1 的维度。例如，如果 A 是 3×1×2 数组，则 squeeze(A) 返回 3×2 矩阵。

%   For example,
%       squeeze(rand(2,1,3))
%   is 2-by-3.
%
%   See also SHIFTDIM.

%   Copyright 1984-2010 The MathWorks, Inc. 

if nargin==0 
  error(message('MATLAB:squeeze:NotEnoughInputs')); 
end

if ~ismatrix(a)
  siz = size(a);
  siz(siz==1) = []; % Remove singleton dimensions.
  siz = [siz ones(1,2-length(siz))]; % Make sure siz is at least 2-D
  b = reshape(a,siz);
else
  b = a;
end

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
function [g,c,d] = gcd(a,b)
%GCD    Greatest common divisor.
%   G = GCD(A,B) is the greatest common divisor of corresponding elements
%   of A and B.  The arrays A and B must contain integer values and must be
%   the same size (or either can be scalar). GCD(0,0) is 0 by convention;
%   all other GCDs are positive integers.
%
%   [G,C,D] = GCD(A,B) also returns C and D so that G = A.*C + B.*D.
%   These are useful for solving Diophantine equations and computing
%   Hermite transformations.
%
%   Class support for inputs A,B:
%      float: double, single
%      integer: uint8, int8, uint16, int16, uint32, int32, uint64, int64
%
%   See also LCM.

%   References:
%   Knuth, Donald, The Art of Computer Programming, Vol. 2, Addison-Wesley:
%      Reading MA, 1973. Section 4.5.2, Algorithms A and X.
%
%   Thanks to John Gilbert for the original version
%   Copyright 1984-2017 The MathWorks, Inc.

if ~isequal(size(a),size(b)) && ~isscalar(a) && ~isscalar(b)
    error(message('MATLAB:gcd:InputSizeMismatch'))
end

if ~isreal(a) || ~isequal(round(a),a) || any(isinf(a(:))) || ...
   ~isreal(b) || ~isequal(round(b),b) || any(isinf(b(:)))
    error(message('MATLAB:gcd:NonIntInputs'))
end

if ~isscalar(a)
    siz = size(a);
else
    siz = size(b);
end
a = a(:); 
b = b(:);

if isinteger(a)
    if ~(strcmp(class(a),class(b)) || (isa(b,'double') && isscalar(b)))
        error(message('MATLAB:gcd:mixedIntegerTypes'))
    end
    classin = class(a);
    if isa(b,'double') && (b > intmax(classin) || b < intmin(classin))
        error(message('MATLAB:gcd:outOfRange'));
    end
    inttype = true;
elseif isinteger(b)
    if ~(isa(a,'double') && isscalar(a))
        error(message('MATLAB:gcd:mixedIntegerTypes'))
    end
    classin = class(b);
    if a > intmax(classin) || a < intmin(classin)
        error(message('MATLAB:gcd:outOfRange'));
    end
    inttype = true;
else
    classin = superiorfloat(a,b);
    largestFlint = flintmax(classin);
    if any(abs(a) > largestFlint) || any(abs(b) > largestFlint)
        warning(message('MATLAB:gcd:largestFlint'));
    end
    inttype = false;
end

if nargout <= 1
    % intmin in signed integers requires special handling
    iminIndex = [];
    if inttype
        imin = intmin(classin);
        if imin < 0
            iminIndex = xor(a == imin, b == imin);
        end
    end
    u = max(abs(a),abs(b));
    v = min(abs(a),abs(b));
    u(iminIndex) = u(iminIndex)/2;
    vnz = v>0;
    while any(vnz)
        t = rem(u,v);
        u(vnz) = v(vnz);
        v(vnz) = t(vnz);
        vnz = v>0;
    end
    g = reshape(u,siz);
else
    if inttype
        if intmin(classin) == 0    % unsigned integers not supported
            error(message('MATLAB:gcd:unsupportedType'));
        end
    end
    len = prod(siz);
    if issparse(a) || issparse(b)
        u = spalloc(len,3,nnz(a)+len);
    else
        u = zeros(len,3,classin);
    end
    u(:,1) = 1;
    u(:,3) = a;
    if issparse(b)
        v = spalloc(len,3,nnz(b)+len);
    else
        v = zeros(len,3,classin);
    end
    v(:,2) = 1;
    v(:,3) = b;
    vnz = v(:,3)~=0;
    while any(vnz)
        if inttype
            q = idivide(u(:,3),v(:,3));
        else
            q = fix( u(:,3)./v(:,3));
        end
        t = u - v .* q;
        u(vnz,:) = v(vnz,:);
        v(vnz,:) = t(vnz,:);
        vnz = v(:,3)~=0;
    end
    
    
    g = reshape(u(:,3),siz);
    c = reshape(u(:,1),siz).*sign(g);
    d = reshape(u(:,2),siz).*sign(g);
    g = abs(g);
    % correct overflow conditions in signed integers
    if inttype
        overflow1 = reshape(a == intmin(classin) & b == -1, siz);
        overflow2 = reshape(a == -1 & b == intmin(classin), siz);
        g(overflow1 | overflow2) = 1;
        c(overflow1) = 0;
        d(overflow1) = -1;
        c(overflow2) = -1;
        d(overflow2) = 0;
    end
end

1
2
f = fullfile(filepart1,...,filepartN) 根据指定的文件夹和文件名构建完整的文件设定。

1
2
3
const = physconst(name) returns the value of the physical constant const 
specified by the name argument.

1
2
3
Y = typecast(X,type) 将 X 的位模式转换为 type 指定的数据类型，而不更改基础数据。
X 必须为由非复数数值组成的满标量或满向量。

1
2
3
Y = swapbytes(X) 将数组 X 中每个元素的字节排序从 little endian 转换为 big endian
（或相反）。输入数组的所有元素必须是完整的非复数数值元素。

1
2
3
[file,path] = uigetfile('C:DocumentsWork*.png',...
                        'Select an Image File')

1
2
3
4
5
6
7
Root 对象是图形对象树的根。Root 属性包含有关图形环境和图形系统的当前状态的信息。
使用圆点表示法引用特定的对象和属性。
获取主显示画面的大小
get(groot, 'ScreenSize');
使用图形根对象为其他类型的对象设置根级别的默认值。例如，将以后所有图窗的默认颜色图设置为 summer 颜色图。
set(groot,'DefaultFigureColormap',summer)

1
2
3
4
X = NaN(sz1,...,szN) 返回由 NaN 值组成的 sz1×...×szN 数组，
其中 sz1,...,szN 指示每个维度的大小。
例如：NaN(3,4) 返回一个 3×4 的矩阵。

1
2
3
B = repmat(A,n) 返回一个数组，该数组在其行维度和列维度包含 A 的 n 个副本。
A 为矩阵时，B 大小为 size(A)*n。

1
2
3
4
5
6
7
8
9
10
11
12
patch(X,Y,C) 使用 X 和 Y 的元素作为每个顶点的坐标，以绘制一个或多个填充多边形区域。
patch 以您指定顶点的顺序连接这些顶点。要创建一个多边形，请将 X 和 Y 指定为向量。
要创建多个多边形，请将 X 和 Y 指定为矩阵，其中每一列对应于一个多边形。
C 决定多边形的颜色。
通过将 x 和 y 指定为两列矩阵，创建两个多边形。每一列定义其中一个多边形的坐标。
x2 = [2 5; 2 5; 8 8];
y2 = [4 0; 8 2; 4 0];
patch(x2,y2,'green')
%2、2、8是第一个多边形的x坐标；5、5、8是第二个多边形的y坐标
%4、8、4是第二个多边形的x坐标；0、2、0是第三个多边形的y坐标
%没有明显的顺时针或者逆时针

1
2
3
4
5
6
7
8
9
%通过向类定义中添加 enumeration 代码块可创建枚举类。
%例如，WeekDays 类列举一周中的工作日。

classdef WeekDays
   enumeration
      Monday, Tuesday, Wednesday, Thursday, Friday
   end
end

1
2
noise = bitshift(AA,-4); % noise = AA/2^4

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
close all;
clear all;
clc;
for ii = 1:3
    for jj = 1:3
        
        if ii == 1 && jj == 2
            break;
        end
        disp(['ii = ',num2str(ii),'   ,jj = ',num2str(jj),'   ,aa = ',num2str(ii+jj)]);
    end
end
for ii = 1:3
    for jj = 1:3
        
        if ii == 1 && jj == 2
            continue;
        end
        disp(['ii = ',num2str(ii),'   ,jj = ',num2str(jj),'   ,bb = ',num2str(ii+jj)]);
    end
end

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
ii = 1   ,jj = 1   ,aa = 2
ii = 2   ,jj = 1   ,aa = 3
ii = 2   ,jj = 2   ,aa = 4
ii = 2   ,jj = 3   ,aa = 5
ii = 3   ,jj = 1   ,aa = 4
ii = 3   ,jj = 2   ,aa = 5
ii = 3   ,jj = 3   ,aa = 6
ii = 1   ,jj = 1   ,bb = 2
ii = 1   ,jj = 3   ,bb = 4
ii = 2   ,jj = 1   ,bb = 3
ii = 2   ,jj = 2   ,bb = 4
ii = 2   ,jj = 3   ,bb = 5
ii = 3   ,jj = 1   ,bb = 4
ii = 3   ,jj = 2   ,bb = 5
ii = 3   ,jj = 3   ,bb = 6

1
2
3
4
5
6
7
8
9
10
11
12
13
classdef (Attributes) ClassName < SuperclassName
   enumeration
      EnumName
   end
end
% 例如
classdef Assigned < int32
   enumeration
      Failed        (0)
      succeed	    (1)
   end
end