Thanks for all the advice. Much appreciated. The problem has been sorted out now. Apparently its to do with the fact that PDL treats an N-PDL as a row-vector and a 1xN-PDL as a column vector, unlike Matlab.
This took care of that. 
$X = $A x $B x $C->xchg(0,1) x $D;

[download]
I'm still not quite understanding but hey, it works.

In reply to Re: Why dies this work in matlab and not PDL? by Angharad
in thread Why dies this work in matlab and not PDL? by Angharad

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