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>
>I do not manage
>to understand what a matrix is exactly ... Could someone help me ?
>In an ethymologic dictionary they say it originates from "mater" mother
>in Latin....
You basically have it. Mater = Mother. So the womb or in or from that
which something originates or takes form or develops, like the rock in
which a gem is embedded or a die or mold for casting, etc.