Do we need Mat, Vec, TMmat, Diag, Sym and other matrix types?

[jmh530]

On Tuesday, 13 March 2018 at 10:35:15 UTC, 9il wrote:
> On Tuesday, 13 March 2018 at 04:35:53 UTC, jmh530 wrote:
>> [snip]
>>
>> What's TMMat?
>
> TMat is a transposed matrix. Not sure for now if it would be 
> required.
>

There are some people who like being able to specify a whether a 
matrix has column or row layout. Would an option to control this 
be the same thing?