concatenate cell

i have a cell (symbol {} on the variable list) with a=('kkk', 'lll', 'xxx', 'jjj.xls')

and i want to concatenate a so that i can have

b = ('kkk_lll_xxx_jjj.xls')

thank you

[Alexandros]

They are not with , (commas separated) they are separated with ; so they are one under the other. but i want one string at the end

[Alexandros]

I don't want to separate a because it can be of infinite dimensions. i need to concatenate as much as information i have in the initial cell

Answer 1

[Andrei Bobrov]

a={'kkk', 'lll', 'xxx', 'jjj.xls'}';
out = [a(:)';repmat({'_'},1,numel(a))];
out = [out{:}];
out = out(1:end-1);

variant 2

out = cell(1,2*numel(a)-1);
out(1:2:end) = a;
out(2:2:end) = {'_'};
out = [out{:}];

[Alexandros]

This is perfect but it puts me a '_' also at the end which i dont need

maybe i could delete it with taking only out(1:end-1)?

Answer 2

[Jan]

a = {'kkk'; 'lll'; 'xxx'; 'jjj.xls'}
out = sprintf('%s_', a{:});
out(end) = [];

or:

out = [sprintf('%s_', a{1:end-1}), a{end}];

or:

out = sprintf([repmat('%s_', 1, numel(a)-1), '%s'], a{:});

For very large cell strings, this becomes slow because Matlab forgets to pre-allocate the output properly. Therefore I've written the C-mex function CStr2String:

out = CStr2String(a, '_', 'noTrial')

[Andrei Bobrov]

Hi Jan! +1.

Answer 3

[Alexandros]

This is perfect but it puts me a '_' also at the end which i dont need

maybe i could delete it with taking only out(1:end-1)?

Answer 4

[Alexandros]

This is very helpul guys

Thank you

Answer 5

[Eric Tao]

just type:

b = {strjoin(a,'_')};

Then your b will be a cell as

{'kkk_lll_xxx_jjj.xls'}