Filtering the data using IF

Hi, I have 2 variables (matrixes) Time (5810x1) and DF_x (5810x1). I'd like to display only DF_x rows that are equal to 0 and its Time (each row in matrix called Time corresponds to the same row in matrix called DF_x). I have created a code shown below but it doesn't work. In the DF_x matrix there are 12 rows with a value equal to 0, which means that the code should display 12 rows and 2 colums- DF_x and a given time for each value of DF_x. Unfortunately, the result shows more than 1300 DF_x rows all with zeros (which is not correct). It also shows 12 Time rows with a correct time but the rest is all zeros as well. Could you please help me to make this work? Thank you!

    [m,n]=size(DF_x);
for i=1:m
    for j=1:n
        if DF_x(i,j)==0 
            DF_acas(i,j)=DF_x(i,j);
            Time_acas(i,j)=Time(i,j);      
        end
    end
end
acas=[Time_acas DF_acas];

Answer 1

[KSSV]

    idx=DF_x==0;
    DF_x0=DF_x(idx);
    t0=Time(idx);
    iwant=[t0 DF_x0];

[Jakub Nosek]

Thanks! It works!