Combine 2 datasets and include the duplicates

I have two datasets, the first is a list of postcodes gathered from a survey, the second is a matrix that cross-references all postcodes with the areas they are in. I want to generate a column listing the areas that the survey postcodes represents.

The part I am having trouble with is that in some cases, one postcode can correspod to mutiple areas, in these situations I want to include both areas in the new column.

I've tried joining the tables, but the standard Join command seems to have issues with there being duplicate values

Answer 1

[ANKUR KUMAR]

clc
clear
postcodes=randi(20,50,1);
areas=randi(10,50,5);

area_unique=unique(areas);

for ii=1:length(area_unique)
    [xx,yy]= find(areas==area_unique(ii));
    postcode_ref{ii}=unique(xx)';
end

If it helps you, then it's good. Otherwise, if you can provide the datset (or sufficient variables in a mat file), it owuld help us to help you.

Answer 2

[Seth Furman]

Check out innerjoin and outerjoin.

https://www.mathworks.com/help/matlab/ref/innerjoin.html

https://www.mathworks.com/help/matlab/ref/outerjoin.html