Hey,

So I've been using Eigen for a while now and found my way around, but there's something I can't find, so I wanted to ask:

Is there anything like Octave's / Matlab's find() in Eigen? E.g., like this

>> A = [1 2 3 4 5]
A =
1 2 3 4 5

>> find(A >= 3)
ans =
3 4 5

>> find(A < 2)
ans = 1

It returns a vector of indexes, for which the given boolean holds true.

We don't have that yet. We first have to support integer array as indices to make that feature useful. However, we have a (A > 3).select(E,F) mechanism which might be enough in your case?

Not exactly what I need, but I wrote some util function for my own purposes, not that important anyway.

As for the select() -- thanks, hadn't noticed that, I'm sure it'll come in handy.