Matching unequal cell arrays

I have two unequal arrays and I want to match them to produce one array such that the unmatched cells are left empty i.e

A = {124,252,1252,225,598,999}
B = {598,'plant';
1252,'nil';
252,'blue'}

The result C;

C = {124,[];
252,'blue';
1252,'nil';
225,[];
598,'plant';
999,[]}

Answer 1

[TADA]

A = {124,252,1252,225,598,999};
B = {598,'plant';...
     1252,'nil';...
     252,'blue'};
 
 [~, Ai_member, Bi_member] = intersect([A{:}], [B{:,1}]);
 
 C = [A(:), cell(numel(A), 1)];
 [C{Ai_member, 2}] = B{Bi_member, 2}

[Ronald]

This one works but when an item is repeated in A it leaves them empty, i.e

A = {124,252,252,1252,225,225,598,598,999};
B = {598,'plant';...
     1252,'nil';...
     252,'blue'};
 
 [~, Ai_member, Bi_member] = intersect([A{:}], [B{:,1}]);
 
 C = [A(:), cell(numel(A), 1)];
 [C{Ai_member, 2}] = B{Bi_member, 2}
Gives:
{[ 124]}    {0×0 double}
    {[ 252]}    {'blue'    }
    {[ 252]}    {0×0 double}
    {[1252]}    {'nil'     }
    {[ 225]}    {0×0 double}
    {[ 225]}    {0×0 double}
    {[ 598]}    {'plant'   }
    {[ 598]}    {0×0 double}
    {[ 999]}    {0×0 double}

[TADA]

In that case, ismember should do the trick

it returns a logical index (flags) and the matching indices in B

for matching cells, the logical index is true and the B index has the index of the match

and for unmatched cells both indices have the value zero

A = {124,252,252,1252,225,225,598,598,999};
B = {598,'plant';...
     1252,'nil';...
     252,'blue'};

[flags, Bidx] = ismember([A{:}], [B{:,1}]);

C = [A(:), cell(numel(A), 1)];
[C{flags, 2}] = B{bidx(bidx > 0), 2}

C =

  9×2 cell array

    {[ 124]}    {0×0 double}
    {[ 252]}    {'blue'    }
    {[ 252]}    {'blue'    }
    {[1252]}    {'nil'     }
    {[ 225]}    {0×0 double}
    {[ 225]}    {0×0 double}
    {[ 598]}    {'plant'   }
    {[ 598]}    {'plant'   }
    {[ 999]}    {0×0 double}

[Ronald]

This is really good. Thank you very much!

Answer 2

[Stephen23]

Using tables:

>> TA = cell2table(A(:))
TA = 
    Var1
    ____
     124
     252
     252
    1252
     225
     225
     598
     598
     999
>> TB = cell2table(B'')
TB = 
    Var1     Var2  
    ____    _______
     598    'plant'
    1252    'nil'  
     252    'blue' 
>> T = outerjoin(TA,TB,'MergeKeys',true)
T = 
    Var1     Var2  
    ____    _______
     124    ''     
     225    ''     
     225    ''     
     252    'blue' 
     252    'blue' 
     598    'plant'
     598    'plant'
     999    ''     
    1252    'nil' 

Note that the output rows are sorted by the joining key. To keep the original order:

>> [T,X] = outerjoin(TA,TB,'MergeKeys',true);
>> T(X,:) = T
T = 
    Var1     Var2  
    ____    _______
     124    ''     
     252    'blue' 
     252    'blue' 
    1252    'nil'  
     225    ''     
     225    ''     
     598    'plant'
     598    'plant'
     999    ''