<div dir="ltr">The Eigen tensor module (easily available via RcppEigen as far as I can tell) might be worth a look: <a href="http://eigen.tuxfamily.org/index.php?title=Tensor_support">http://eigen.tuxfamily.org/index.php?title=Tensor_support</a> </div><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Apr 18, 2018 at 3:13 AM, Dirk Eddelbuettel <span dir="ltr"><<a href="mailto:edd@debian.org" target="_blank">edd@debian.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class=""><br>
On 18 April 2018 at 01:56, Avraham Adler wrote:<br>
| May not be possible. See<br>
| <a href="https://stackoverflow.com/questions/16105548/4-dimensional-matrix-in-armadillo" rel="noreferrer" target="_blank">https://stackoverflow.com/<wbr>questions/16105548/4-<wbr>dimensional-matrix-in-<wbr>armadillo</a><br>
<br>
</span>Avi is correct.<br>
<br>
Armadillo, as clearly documented, knows<br>
<br>
  vector   1d<br>
  matrix   2d<br>
  cube     3d<br>
  fields   lists of matrices or cubes<br>
<br>
plus sp_mat for sparse matrices.  No 4d arrays.<br>
<span class="HOEnZb"><font color="#888888"><br>
Dirk<br>
<br>
-- <br>
<a href="http://dirk.eddelbuettel.com" rel="noreferrer" target="_blank">http://dirk.eddelbuettel.com</a> | @eddelbuettel | <a href="mailto:edd@debian.org">edd@debian.org</a><br>
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