Error too many input arguments using equals equals

Each row of the table want contains information about a specific person. Each row of the cell array (I tried having it be a table and got different errors) roster has information about a specific person and their subject ID. I want to get the subject ID of every person in the table want. To do this, I am saying (I think I'm saying) for every row in want to find the row in roster that has the same value in column 3 as want's column 3 and the same value in roster's column 2 as want's column 2. Then the array PTID will print all of the subject IDs that I want.

Errors:

-line 5: too many input arguments for == (it does this with and without the and)

-line 5: I think the {:,3} and {:,2} might not necissarily mean the same row in both cases

-line 1 & 2 (currently not an error, but might cause other errors): having want be a table and roster be a cell doesn't allow it to do the same things as matrices does, but I am unable to turn them into matrices.

-previously I had the error == was an undefined operator for cell type, but fixed it by using curly brackets

1    want=readtable('miniStable_MCI.csv');%the file to copy into matrix
2    roster = table2cell(readtable('miniROSTER.csv'));
3    PTID=zeros(4439);
4    for j = 1:4439 
5        rosterrow=find((roster{:,3}==want{j,3})&(roster{:,2}==want{j,2}));%row 3
6        ...has RID, row 2 has site ID, and both values must be the same as the
7        ...2 values in the other matrix
8        PTID(j)=roster(rosterrow,5);%roster has subject ID in column 5
9    end
sprintf(PTID)

example rows of want:

[ADNI1 39 267 2035; ADNI1 5 267 50; ADNI2 39 19 50]

example row of roster:

[ADNI1 39 82 50 149_S_0082; ADNI1 14 19 002_S_0019; ADNI1 5 267 50 014_S_0267]

So row 2 of want would correlate with row 3 of roster and output subject ID 014_S_0267]

Thank you so much!!

Answer 1

[Voss]

"I tried having it be a table and got different errors"

Let me keep both want and roster as tables.

want = table({'ADNI1';'ADNI1';'ADNI3'},[39; 5; 39],[267; 267; 19],[2035; 50; 50])

want = 3×4 table
      Var1       Var2    Var3    Var4
    _________    ____    ____    ____

    {'ADNI1'}     39     267     2035
    {'ADNI1'}      5     267       50
    {'ADNI3'}     39      19       50

roster = table({'ADNI1';'ADNI1';'ADNI1'},[39;14;5],[82;NaN;267],[50;19;50],{'149_S_0082';'002_S_0019';'014_S_0267'})

roster = 3×5 table
      Var1       Var2    Var3    Var4         Var5     
    _________    ____    ____    ____    ______________

    {'ADNI1'}     39      82      50     {'149_S_0082'}
    {'ADNI1'}     14     NaN      19     {'002_S_0019'}
    {'ADNI1'}      5     267      50     {'014_S_0267'}

for-loop solution:

N = size(want,1);
PTID = cell(N,1);
PTID(:) = {'<NO MATCH>'};
for jj = 1:N
    rosterrow = find((roster{:,3}==want{jj,3})&(roster{:,2}==want{jj,2}), 1);
    if ~isempty(rosterrow)
        PTID(jj) = roster{rosterrow,5};
    end
end

disp(PTID)

    {'<NO MATCH>'}
    {'014_S_0267'}
    {'<NO MATCH>'}

vectorized solution:

N = size(want,1);
PTID = cell(N,1);
PTID(:) = {'<NO MATCH>'};
[ism,idx] = ismember(want{:,[2 3]},roster{:,[2 3]},'rows');
PTID(ism) = roster{idx(ism),5};

disp(PTID)

    {'<NO MATCH>'}
    {'014_S_0267'}
    {'<NO MATCH>'}