Extract sub-matrix based on conditions of specific columns in matlab - matlab

Question

I want to Select a sub-matrix x7992 based on conditions of Certain columns of original data matrix. Specifically, the original matrix is 23166-by-9, follow a original Gauss code
x7992 =selif(data,data[.,col_coh].==0 .and data[.,col_year].<=1992);
I rewrite this in matlab with
x7992 = data(data(:,col_coh)==0 & data(:,col_year)<=1992);
col_coh，col_year are predefined column number.
However, rather than give me a sub-matrix, the above line of code only give me a single row (23166-by-1),it's not what I want (and not the real result base on this condition).So how to fix it? thank you.
--- Update -----
The data matrix is like (I omit other columns because only first 3 cols are relevant to selection), the first column is id for individuals
1 1979 0
1 1980 0
1 1981 1
1 1982 0
1 1983 1
2 1990 0
2 1991 0
2 1992 0
2 1993 1
3 1985 0
3 1986 0
3 1987 0
Based on the conditions, what I want is a submatrix from data, which excludes those rows with value>1992 in the second column and value=1 in the third one

Answer 1

You only get a single column vector as output since your condition vector is returned as a single 23166x1 vector.
To get the entire row of values you need to add a colon as a second argument.
I've splitted the example in two lines to make more readable.
condIdx = data(:,col_coh)==0 & data(:,col_year)<=1992;
x7992 = data( condIdx, :);
If you want specific columns in your result matrix, just put the column number in a vector instead of the colon operator.
colsInResult = [1 2 3];
x7992 = data( condIdx, colsInResult);

Answer 2

Based on the example that you have given, the following will do this:
data(data(:,2)<=1992 & data(:,3)~=1,:)
which gives this output:
1 1979 0
1 1980 0
1 1982 0
2 1990 0
2 1991 0
2 1992 0
3 1985 0
3 1986 0
3 1987 0