How to search a table for a string

Hi, I have a table of data. One of these columns includes a column which I have labelled 'Participant Data'

I want to search 'Participant Data' for a particular string and return all the index of this table when it does pop up.

Additionally if I have 2 arrays of indices, how to return just the numbers that are in both indices?

Thanks!

[dpb]

1. See strfind, contains and friends,
2. intersect

Answer 1

[Abhisek Pradhan]

Searching a table for a string can done using find and strcmp. A combination of both function can be used to search a string:

find(strcmp('YourString',Table));

Refer the following link for model details.

https://www.mathworks.com/matlabcentral/answers/2015-find-index-of-cells-containing-my-string

[Lauren Dana]

Oddly enough I'm returning no results from that, even when I know that the table contains the string I'm searching for.

[dpb]

Well, we can't debug what we can't see...attach a sample data file with the subject data and the code that reproduces the problem.

At least one possible cause can be that strfind is case-sensitive so has to match case as well.

Alternatively, we have no idea what "table" means in the context in which you're using it -- a Matlab table is a whole different animal and strcmp() doesn't work on the table itself; it'll needs be the content of a variable/column within the table -- and depending on that content.

[Samad]

strcmp does not work with table, it works with cell. First we have to convert table into cell.

Run the following code

name=["sam"; "jack"];
age=[20'; 27]; height=[4; 5];
tab=table(name, age, height)

tab = 2×3 table
     name     age    height
    ______    ___    ______

    "sam"     20       4   
    "jack"    27       5   

extract the name sam

idx=strcmp("sam",tab)

idx = logical
   0

[dpb]

" First we have to convert table into cell...."

No, not really. You do have to reference the variable of interest inside the table, though, yes...

Try the following instead...

name=["sam"; "jack"];
age=[20'; 27]; height=[4; 5];
tab=table(name, age, height);
tab(strcmp(tab.name,'sam'),:)

ans = 1×3 table
    name     age    height
    _____    ___    ______

    "sam"    20       4   

Or, with new string variable functions,

tab(matches(tab.name,'sam'),:)

ans = 1×3 table
    name     age    height
    _____    ___    ______

    "sam"    20       4