I have 2 files: one with department names (dpt) ; tree species (1 dpt could have many species); and a 3rd var (index_a). the other with dpt and forested region names (1 dpt could have many forested reg.)

I want to multiply file 1 by file 2, in order to obtain for each "forested region within a dpt" the info about the "dpt species index" line .

It is not just a normal merge... but I am lacking experience to do the coding.

Could someone help me please!

Thank in advance!

Here is an example of want I want to do

File 1 dpt tree_sp index 1 1 5 1 2 5 1 3 4 2 1 1 ...

File 2 dpt reg 1 1 1 2 2 1 ...

Final file should look like dpt reg tree_sp index 1 1 1 1 5 1 1 2 5 1 1 3 4 1 2 1 5 1 2 2 5 1 2 3 4 2 1 1 1 ...