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Re: More /.{I->-1} craziness

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  • Subject: [mg106235] Re: More /.{I->-1} craziness
  • From: Vince Virgilio <blueschi at>
  • Date: Wed, 6 Jan 2010 05:56:50 -0500 (EST)
  • References: <> <hhhmn8$o9t$>

On Jan 5, 1:43 am, Richard Fateman <fate... at> wrote:


> Are you describing Mathematica here?   It seems to me that it is an
> exception that Head[a+b*I] is Plus, but Head[3+4I] is Complex.


Please explain why that is an exception.

'a' and 'b' can be anything, not necessarily numbers. Hence a + b*I
can be anything as well (say, notebookA + notebookB * I). Not so for
3, 4, and 3 + 4*I.

Vince Virgilio

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