Re: Numeric errors???

[Dirk Laurie]

Christophe TROESTLER skryf:
> Hi,
> 
> I am a beginner using Octave.  The two sets of functions below (H1,
> H2, H3 and H11, H22, H33) should give the same result.  However, the
> final results are dramatically different.  Anyone can help me with
> this?  (Probably a stupid misunderstanding of mine.)
> 
Your expressions are all of the form BIG1-BIG2, where the two operands
are mathematically equal but have been computed by different algorithms.
Although the final results look "dramatically different", the same cannot
be said of BIG1 and BIG2.  They look undramatically the same except in the
last digit.

Consult any book with a title like "Numerical Analysis" for a good
explanation.

Dirk Laurie



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