[Jprogramming] Reshaping 3+d matrices

[Rob Hodgkinson]

Hi John, did you try dyadic transpose (x |: y) where x is a reposition vector of dimensions …

   (1 0 2 |: mat) -: |:"2|:"3|:"2 mat
1

…/Rob

> On 24 Jan 2018, at 6:21 pm, 'Jon Hough' via Programming <programming at jsoftware.com> wrote:
> 
> I have a 3d matrix of shape  a b c say. But I want to reshape it to have shape b a c, while still keeping data positional integrity.
> So doing (b,a,c) $, myMatrix 
> will not work, as it destroys the relative positional relations between items.
> e.g.
> 
> mat =: ?  3 10 20 $ 0 NB. shape 3x10x20
> 
> I can reshape it using 
> |:"2|:"3|:"2 mat
> 
> But this seems ugly, and based on past experience there is usually an obvious / simple / elegant / in-built way to
> do it. It seems like there is a nicer way to do it.
> 
> Any ideas?
> 
> Thanks,
> Jon
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