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Re: Filtering
From: |
Francesco Potorti` |
Subject: |
Re: Filtering |
Date: |
Mon, 28 Feb 2005 18:39:15 +0100 |
octave> a=[0 1 0]
a =
0 1 0
octave> b=logical(a)
b =
0 1 0
octave> [5 6 7](a)
error: invalid vector index = 0
octave> [5 6 7](b)
ans = 6
octave> isbool(a)
ans = 0
octave> isbool(b)
ans = 1
Wow! This looks significant to me, and now I understand some strange
behaviour I observed in the past.
So, in the example above, a and b are in fact different, and from the
output of whos I see that each bool value occupies one byte. However,
when used with arithmetic operators, boolean are promoted to numeric.
So, boolean values can be used as 1-0 matrix indices, and they occupy
only one byte per element, rather than eight. Are these the only
differences between numeric and boolean values?
--
Francesco Potortì (ricercatore) Voice: +39 050 315 3058 (op.2111)
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-------------------------------------------------------------
- Filtering, Hamish Allan, 2005/02/28
- RE: Filtering, Hall, Benjamin, 2005/02/28
- Re: Filtering,
Francesco Potorti` <=