<p>Armadillo supports in-place transpose now.</p>

<p><a href="https://cloud.githubusercontent.com/assets/3522399/6196970/92ebc60e-b3ef-11e4-9eac-eccbcc71bc66.png" target="_blank"><img src="https://cloud.githubusercontent.com/assets/3522399/6196970/92ebc60e-b3ef-11e4-9eac-eccbcc71bc66.png" alt="rplot" style="max-width:100%;"></a><br>
size in MB, time in seconds.<br>
0 - transpose, using mat = mat.t();<br>
1 - transpose, using inpalce_trans(mat). looks like the same as 0;<br>
2 - inplace_trans(mat, "lowmem");</p>

<p>End memory usage snapshots:<br>
<a href="https://cloud.githubusercontent.com/assets/3522399/6196968/92eb2686-b3ef-11e4-9aa7-d7bd0cff4a2c.png" target="_blank"><img src="https://cloud.githubusercontent.com/assets/3522399/6196968/92eb2686-b3ef-11e4-9aa7-d7bd0cff4a2c.png" alt="lowmem_transpose" style="max-width:100%;"></a><br>
<a href="https://cloud.githubusercontent.com/assets/3522399/6196969/92eb9cc4-b3ef-11e4-9408-bd27e6c9cd9f.png" target="_blank"><img src="https://cloud.githubusercontent.com/assets/3522399/6196969/92eb9cc4-b3ef-11e4-9408-bd27e6c9cd9f.png" alt="simple_transpose" style="max-width:100%;"></a></p>

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