Ah, excellent, that makes sense. In practice this is how we'll be doing it
anyway.

On Friday, March 27, 2015, Matt Bauman <[email protected]> wrote:

> On Friday, March 27, 2015 at 8:21:10 AM UTC-4, Sebastian Good wrote:
>>
>> Forgive my ignorance, but what is Cartesian indexing?
>>
>
> There are two ways to iterate over all elements of an array: Linear
> indexing and Cartesian indexing. For example, given a 2x3 matrix, linear
> indexing would use just one index from 1:6, whereas Cartesian indexing
> specifies indices for both dimensions: (1,1), (1,2), (2,1), ...
>
>
> If an array isn't stored continuously in memory for linear indexing,
> converting to the Cartesian indices is very expensive (because it requires
> integer division, which is a surprising slow). The new `eachindex` method
> in 0.4 returns an iterator to go over all the Cartesian indices very
> quickly.
>


-- 
*Sebastian Good*

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