find indices of string matches from a cell array by thier endings

I want to find the indices of a cell array whose memembers end with a specific string. Eg.

A={'aAbc' 'dgbc' 'bebd' 'fabc' 'fa  '}

Now if I want to find out the indices of the strings which end either with two characters'bc' or ' ' (empty), which command in Matlab would be suitable for this ?

Answer 1

[Chad Greene]

Do it without loops to make it a bit faster:

A={'aAbc' 'dgbc' 'bebd' 'fabc' 'fa  ' 'abcd' 'abcdkads' 'a' 'snacks bc'};

myindices = ~cellfun(@isempty,regexp(A,'bc$'))

[Dishant Arora]

It makes me feel stupid. +1

[Chad Greene]

I just saw the bit about "or ends in empty". Here's a fix:

myindices = ~cellfun(@isempty,regexp(A,'bc$')) + ~cellfun(@isempty,regexp(A,'  $'))

[Meh]

Thanks. It works. May I ask you what is the task of @isempty in the code?

[Chad Greene]

If regexp(A,'bc$') were an array of numbers, you could put it inside a function like isempty(regexp(A,'bc$')). However, regexp(A,'bc$') is not an array of numbers, it's an array of cells. You can operate on cells as if they were numbers if you use cellfun(@FUNCTION,...), hence, cellfun(@isempty,regexp(A,'bc$')).

Answer 2

[Jos (10584)]

You can use REGEXP to find a specific string property. Moreover you can combine various properties using the separator |

A={'aAbc' 'dgbc' 'bebd' 'fabc' 'fa  '}
indexA = find(~cellfun(@isempty, regexp(A,'bc$| $')))

[Chad Greene]

Ah, good thinking. I knew there'd be a way to include the or operator in regexp.

Answer 3

[Sara]

strcmp or strcmpi

Example of how you could do it (not elegant but works):

A={'aAbc' 'dgbc' 'bebd' 'fabc' 'fa  '};
str = 'bc';
index = zeros(length(A),1);
str_length = length(str);
for i = 1:length(A)
    k1 = strcmp(A{i}(end-str_length+1:end),str);
    k2 = strcmp(A{i}(end-str_length+1:end),blanks(str_length));
    if(k1 ~= 0 || k2 ~= 0)
        index(i) = i;
    end
end
index = index(index>0);

Answer 4

[Dishant Arora]

 A  = {'aAbc' 'dgbc' 'bebd' 'fabc' 'fa  '};
fun = @(x) (length(x) == regexp(x , 'bc' , 'end'))
B   = cellfun(fun,A,'Un',0);
for ii=1:length(B)
    if isempty(B{ii})
        B{ii} = false;
    end
end
Idx = A(cell2mat(B))

There might be better ways to do it, but this is what I come up with.