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Dear all,<br>
<br>
I note that sum([]) yields 0 instead of []. This is somewhat
contradictory with the documented behavior that [] + n yields []
regardless of the type of n<br>
<br>
I allso find that prod([]) yields 1. This is even stranger. The
common feature is that both are the respective neutral element of
the operations.<br>
<br>
Interestingly, cumsum and cumprod applied to [] yield the expected
result, []<br>
<br>
</font><font face="Courier New">Besides, type([]) is 1 (constant).
Somehow it is asuming an empty matrix is by default a container
for constants, even in csses such as the following:<br>
<br>
a = %s<br>
b = a(1:$-1) <br>
<br>
where b is an empty sub-vector of a polynomial vector.<br>
<br>
None of these behaviors seem to be documented. If intentional,
they should be documented.<br>
<br>
Regards,<br>
<br>
Federico Miyara<br>
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