matlab - How to select rows from character array that match char string and save them in a new array? -


i have char array contains list of files names (each row 1 file) (char, 526x26)

val =  0815_5275_uba_a_1971.txt   0815_5275_uba_a_1972.txt   0823_6275_uba_a_1971.txt   0823_6275_uba_a_1972.txt   0823_6275_uba_a_1973.txt ...

i have variable

b = '0815_5275'

i'd select rows (filenames) start b , save them in new array c.

this should simple, somehow can't make work. i've got this:

c = a(a(:,1:9) == b);

but error message:

error using  ==  matrix dimensions must agree.

i not know in advance how many rows match, can not pre-define empty array.

thanks, appreciated!

try ismember(a(:, 1:numel(b)), b, 'rows') rather logical vector indexes rows want

and now

a(c,:) extract rows

the reason you're getting dimension mismatch error because a(:,1:9) has many rows b has 1 , matlab not automatically broadcast octave or python. using either repmat or bsxfun in case ismember correct function choose.


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