My question is very similar to Vertical alignmnent in tabularx X column type and there seems to be many similar questions so hopefully I haven't missed the answer somewhere.
However, I would like to create a new column that is a copy of tabularx X column, with the difference being the new column Y is an m column compared to a p column (which X is by default as described in the docs).
\tabularxcolumn - The default denition of X is p{#1}.
\def\tabularxcolumn#1{p{#1}}
So I would like to define a new column type like
\newcolumntype{Y}{>{\centering\arraybackslash}X}
and then convert the Y column type to m instead of p as it would currently be. That way I can leave X as it's original definition. If I use
\renewcommand{\tabularxcolumn}[1]{>{\small}m{#1}}
Then X is changed to an m column which is not desired. I would need something like
\renewcommand{Y}[1]{>{\small}m{#1}}
But that doesn't work.
Thanks for any help,

XandYcolumns in a single table? – Werner Oct 11 '18 at 18:00ptype X column and amtype X column if possible. – Prevost Oct 11 '18 at 18:02