Matrix row and column headers

I have created a 15 x 15 arrray called M.

This array should have 15 city names going across the top and then the same 15 city names going across the side. Row & Column headers. I have made the array and row header, I cannot make the column header for some peculiar reason.

M = [0,1...] //my matrix

Rows = {'Portland'; 'St. Louis'; ... } //works fine i get a Rows list that is 15 x 1

Columns = {'Portland', 'St. Louis', ... } // My attempt to make a 1 x 15 column list. Fails everytime.

Can someone help me to make a columns header then add it and my row headers to my Array? I have looked up many questions but I cannot get past making the columns header.

Answer 1

[Akshat]

Hi @Jackson Contreras,

To give row and column headers to your matrix in MATLAB, I would strongly recommend using the data structure called "table" in MATLAB.

There is a function called "array2table" in MATLAB, using which you can make a pre existing matrix into a table, with row headers and column headers.

The documentation regarding "array2table" can be found on this link:

https://www.mathworks.com/help/matlab/ref/array2table.html

A boilerplate code to suit your use case can be seen as follows:

M = randi(100, 15, 15); % Replace with your actual data

Rows = {'Portland'; 'St. Louis'; 'New York'; 'Los Angeles'; 'Chicago'; 
        'Houston'; 'Phoenix'; 'Philadelphia'; 'San Antonio'; 'San Diego';
        'Dallas'; 'San Jose'; 'Austin'; 'Jacksonville'; 'Fort Worth'};

Columns = {'Portland', 'St. Louis', 'New York', 'Los Angeles', 'Chicago', 
           'Houston', 'Phoenix', 'Philadelphia', 'San Antonio', 'San Diego',
           'Dallas', 'San Jose', 'Austin', 'Jacksonville', 'Fort Worth'};
T = array2table(M, 'VariableNames', Columns, 'RowNames', Rows);

disp(T);

                    Portland    Houston    Dallas    St. Louis    Phoenix    San Jose    New York    Philadelphia    Austin    Los Angeles    San Antonio    Jacksonville    Chicago    San Diego    Fort Worth
                    ________    _______    ______    _________    _______    ________    ________    ____________    ______    ___________    ___________    ____________    _______    _________    __________

    Portland           18         92         88          76         15          38          47            67           29          21             100             93           92          47            91    
    St. Louis          29         37          1           4         63          81          28             5           42          59              24              5           88          48            39    
    New York           49         33         77          82         92          94          65            38           77          72              69             53           79          24            15    
    Los Angeles        67         40         19          54         58          59          35            36           72          37              54             90            9          32            98    
    Chicago            12          1         70          43          5          82          81            56           15           2              62             36           54          90            70    
    Houston            37         64         43          78         17          79          57            67           59          75              97             31           22          60            20    
    Phoenix            36         10         84         100          8          99          68             4           63          81              77              8           14          96            10    
    Philadelphia        5         62          8          14         65          88          68            71           95          71              84             38           61          98            68    
    San Antonio        89          1         44          12         64          83          59            99           51          22              98             49           71          71            58    
    San Diego          73         77         23          80         33          25          37            79           70          70              68              5           11          82            50    
    Dallas             78          7         47          82         93          60          60            93           25           1              53             16           37          57             5    
    San Jose           22         55         53           5         67          10          75             6           27           9              29             35           64          66            68    
    Austin             86         85         84          95         43          69          81           100           54          59              12             38           68          38            32    
    Jacksonville       68         17         46          48         70          72          33            39           24          87              72              7           39          21            40    
    Fort Worth         27         49          5           8         35          54          29            74           30           9             100             99           14          77             2    

Let me know in the comments if you have any further questions!