cannot search for index of multiple elements in a larger array

I have an array containing 44 location indices

A =

Columns 1 through 11

1027 1471 1963 2458 2913 3392 3897 4418 4918 5409 5920

Columns 12 through 22

6441 6959 7441 7914 8426 8899 9378 9852 10339 10848 11361

Columns 23 through 33

11876 12368 12880 13404 13928 14454 14973 15477 16021 16528 17004

Columns 34 through 44

17487 17980 18508 19008 19487 19978 20473 20978 21454 21738 22380

>>

I have another smaller array

i =

1027 8426 21738 22380

I need to find the indices of the elements of the smaller array in the larger array

I am trying to use the find command as follows;

>> j=find(A == i)

Gives error message

Matrix dimensions must agree.

note:

size(A)

ans =

1 44

>> size(i)

ans =

1 4

What am I doing wrong?

Answer 1

[Walter Roberson]

You do not promise that there will be exactly one match for each element of i, so you need to do something like

A = [   1027        1471        1963        2458        2913        3392        3897        4418        4918        5409        5920 ...
        6441        6959        7441        7914        8426        8899        9378        9852       10339       10848       11361 ...
       11876       12368       12880       13404       13928       14454       14973       15477       16021       16528       17004 ...
       17487       17980       18508       19008       19487       19978       20473       20978       21454       21738       22380
   ]; 
 i = [1027        8426       21738       22380];
 
 arrayfun(@(VAL) find(A==VAL), i, 'uniform', 0)

ans = 1×4 cell array
    {[1]}    {[16]}    {[43]}    {[44]}

If you can promise exactly one match then

 [~,IDX] = ismember(i, A)

IDX = 1×4

1 16 43 44

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In this later code, any member of i that is not matched will result in an entry of 0 in IDX