How can i create a column vector that sotres PERMNO for all that had positive ret and name this column vector as sample?

PERMNO DateOfObservation prc ret Bid Ask shrout

______ _________________ _______ _________ _________ ______ _______

10026 20201231 155.37 0.072598 155.37 155.48 18954

10028 20201231 5.2 0.125541 5.21 5.25 26925

10032 20201231 78.21 0.046848 78.21 78.29 28823

10044 20201231 4.05 -0.051522 4.05 4.1 6071

10051 20201231 21.99 -0.030851 22.01 22.02 38109

10065 20201231 17.29 0.036571 17.29 17.3 108731

How can i create a column vector that sotres PERMNO for all that had positive ret and name this column vector as sample?

Answer 1

[Voss]

% reproducing your table:
data = num2cell([ ...
    10026         20201231          155.37     0.072598       155.37    155.48      18954
    10028         20201231             5.2     0.125541         5.21      5.25      26925
    10032         20201231           78.21     0.046848        78.21     78.29      28823
    10044         20201231            4.05    -0.051522         4.05       4.1       6071
    10051         20201231           21.99    -0.030851        22.01     22.02      38109
    10065         20201231           17.29     0.036571        17.29      17.3     108731
    ],1);
t = table(data{:},'VariableNames',{'PERMNO' 'DateOfObservation' 'prc' 'ret' 'Bid' 'Ask' 'shrout'})

t = 6×7 table
    PERMNO    DateOfObservation     prc         ret        Bid       Ask        shrout  
    ______    _________________    ______    _________    ______    ______    __________

    10026        2.0201e+07        155.37     0.072598    155.37    155.48         18954
    10028        2.0201e+07           5.2      0.12554      5.21      5.25         26925
    10032        2.0201e+07         78.21     0.046848     78.21     78.29         28823
    10044        2.0201e+07          4.05    -0.051522      4.05       4.1          6071
    10051        2.0201e+07         21.99    -0.030851     22.01     22.02         38109
    10065        2.0201e+07         17.29     0.036571     17.29      17.3    1.0873e+05

% getting PERMNO where ret > 0:
t{t{:,"ret"} > 0,"PERMNO"}

ans = 4×1

10026 10028 10032 10065