Have you tried breaking it up into one multiplication at a time? 
$X = $A x $B;
$X = $X x $C;
$X = $X x $D;

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That should tell you (at least) which of the multiplications PDL thinks has the wrong dimensions. Is it possible to have PDL tell you what dimensions it thinks each variable has?
Caution: Contents may have been coded under pressure.

In reply to Re^2: Why does this work in matlab and not PDL? by Roy Johnson
in thread Why dies this work in matlab and not PDL? by Angharad

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