Re: Re: Just another bug in MMA 3.0
- To: mathgroup at smc.vnet.net
- Subject: [mg7520] Re: [mg7491] Re: [mg7431] Just another bug in MMA 3.0
- From: Paulo Mouat <mouat at mail.telepac.pt>
- Date: Tue, 10 Jun 1997 23:17:53 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Kai Koehler wrote:
> E.g. what do you think about the following quite serious bug, which I
> mailed Wolfram support on april 4th:
>
> Sum[Sum[Log[Log[k+j]],{k,1,n}],{j,1,5}]
>
> gives
>
> 5*Sum[Log[Log[k + j]], {k, 1, n}].
>
> Many other people verified this bug on various machines.
If you want to do a multiple sum, the input should read
Sum[Log[Log[k+j]],{k,1,n},{j,1,5}]
What you have typed is a simple sum over k with a function that has an
unknown j. The j on the outer Sum is a dummy variable, with no
relation to the one in Log[k+j].
This is not a bug. Mathematica simply interpreted what you did type,
which is not quite what you intended to do.
Regards.
--
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