Re: [Vxl-maintainers] outer product on vnl_vector_fixed<T,n>

[Amitha P. <pe...@cs...>]

On Thu 03 Mar 2005, Gehua Yang wrote about changing outer_product API
for fixed vectors:
> Currently, I put the template into a new file called vnl_util_fixed.h. 
> But theoretically it shall replace the outer_product() function in 
> vnl_vector_fixed.h/txx (or it shall not). But I am afraid:
> 
> 1. the include of vnl_matrix_fixed.h in vnl_vector_fixed.h is not
> desired.

You don't have to do that, though. You could make outer_product
non-inline, and leave the instantiation to the
VNL_VECTOR_FIXED_INSTANTIATE macro. Unless you think (or, better,
have tested) that a function call has a huge performance hit.

Another option is to move outer_product to vnl_matrix_fixed.h. This
won't affect clients, since they must be including both anyway.


> 2. the change may break code that depends on current implementation.

This is a bigger issue. I think your proposal is the correct thing,
and we should correct our code appropriately. Probably adding
.as_ref() would solve most cases.

Amitha.