appending an empty list

Hello all,

my code:

list_rats = [];

append(list_rats, Cell.rat);

when Cell.rat is a string. it throws me:

Error using append (line 39) Wrong number of input arguments for obsolete matrix-based syntax.

What should I do?

Thanks in advance

[Jan]

What is the function "append"? Does this appear using MuPad? See: http://www.mathworks.com/help/symbolic/mupad_ref/append.html

[Eli Borodach]

what is mupad? shlould I do include?

Answer 1

[Robert]

The behavior of append is specific to the data types input to it. For the basic types, you are probably better off using

list_rats = [];

a_new_list = [list_rats, Cell.rat];
% or
other_list = [list_rats; Cell.rat];

Also, if you indent your code (two spaces will do) when you type a question, answer, or comment, it will appear in a formatted code block as above.

[Eli Borodach]

I have allready tried it. The problem is that I allways add string at length of 16 characters and than when I add string in length of 17 characters it writes:

Error using vertcat

CAT arguments dimensions are not consistent.

[Robert]

You can append strings horizontally regardless of their length, i.e.

>> ['Hello,', ' ', 'World!']
ans =
Hello, World!

But because MATLAB arrays cannot be ragged, vertical concatenation of varying-length strings will produce an error.

>> ['Hello,'; ' '; 'World!']
Error using vertcat
Dimensions of matrices being concatenated are not consistent.

If you are trying to collect a list of strings without combining them into one string, you should try cell arrays.

>> {'Hello', ',', ' ', 'World!'}
ans = 
    'Hello'    ','    ' '    'World!'
>> {'Hello'; ','; ' '; 'World!'}
ans = 
    'Hello'
    ','
    ' '
    'World!'
>> {'Hello', ','; ' ', 'World!'}
ans = 
    'Hello'    ','     
    ' '        'World!'

Use docsearch cell-arrays to learn more.