How to extract rows from a parent matrix based on column values from a second matrix (child)?

I have 2 matrices: Parent matrix (19564 X 5) and a child matrix (3913 X 3) (sub-matrix of parent). The 3 cols in child matrix and 1st 3 cols in parent matrix are x,y and z - coordinates.

Parent= [x,y,z,A,B]
Child= [x,y,z]

I need to extract 4th and 5th column (A and B) from parent matrix corresponding to x,y,z coordinates in child matrix.

I tried using _ ismember_ function in MATLAB, but it performs a col-wise search and I don't get the desired output.

As output, I need a 3913 X 5 matrix whose 1st 3 cols are exactly same as the child matrix and then 2 additional cols (A and B) from parent matrix.

Answer 1

[Nitika Kandhari]

out = Parent(ismember(Parent(:,1:3), Child, 'rows'), :);

is the solution I found from https://stackoverflow.com/questions/49401494/how-to-extract-rows-from-a-parent-matrix-based-on-column-values-from-a-second-ma Just in case someone else needs to perform a similar task.

Answer 2

[KSSV]

You can specify rows in ismember. It works along with rows also. Read the documentation properly.

[Birdman]

rows option works for cases where both matrices have same number of rows.

[KSSV]

Obviously yes........one has to pick first three columns from Parent.