Re: [eigen] On a flexible API for submatrices, slicing, indexing, masking, etc.

[Lorenzo Botti <bottilorenzo@xxxxxxxxx>]

Regarding the simmetry caveat, what about

seq(a,b,-stride) 

where a<b, as the reverse of

seq(a,b,stride)

Meaning that increasing or decreasing is defined by the sign of stride. The first argument is a strong (inclusive) bound and the second is a weak bound.

Also, would using stride as the first argument allow for omitting the bounds when accessing matrices and vectors?

On Jan 8, 2017 4:45 PM, "Yuanchen Zhu" <yuanchen.zhu@xxxxxxxxx> wrote:

Another remaining issue is that, as I said, all the example here and in the wiki basically assume step > 0. If increment d is dynamic and can be either positive or negative, you have to write something like 

​​

A(sgn(a) <= sgn(d)(4 + d * anyZ) <= sgn(b))

​Sorry I meant

​

​

A(sgn(d)*a <= sgn(d)(4 + d * anyZ) <= sgn(d)*b)​