Re: an old bug on the 85

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Re: an old bug on the 85

I believe this was the message you're looking for:

A colleague and I have found a bug in the TI 85 (ROMS 8,9,10) and 86
(ROM 1.2) with the dot product of two complex vectors.

Now, complex vectors aren't used very often by many of the people who
use TI's, I assume.  I also assume that this is the reason that I
haven't heard about this bug.  Perhaps it hasn't been discovered.

Take this command for example:

dot([(2,3),(-4,6),(-2,0)],[(5,7.2),(2,-5),(-5,7)])

The TI returns:   (3.6,-6.6)

This incorrect.  The correct answer is: (20.4,47.4)

Try any combination of complex vectors.

I thought I would bring this to the attention to you folks especially to
those EE's out there who may need this function to work correctly.

Anyway, I'm going back to the HP48GX.  It can do it correctly.  (Among
having a lot of other additional and nicer features.)  So if there's
anyone out there who care's nothing for this bug and would like to
purchase my 86, then contact me and make an offer.  It's in excellent
shape since I just bought it a month ago.  I just can't live with this
bug.

Thanks.

Clayton Workman
cworkman@raider.crsc.k12.ar.us

stephen soltesz wrote:

> Hello,
>
> I recall less than a year ago someone reporting a bug on the 85
> involving complex numbers and (this is what I've forgotten) either the
> dot() or cross() product.  I played with both using complex numbers and
> didn't see any problem.. but need to know what it was or what caused it,
> so as not to mess any calculations up..
>
> So, if anyone knows to what I am referring, or if it was a different
> function, let me know.  I remember it relating to EE majors, for some
> reason.
>
> thankyou.
> stephen.
>
> --
>         "I will take my hands and weave them to a little house,
>          and there you shall keep a dream--"
>                         --Miriamne. "Winterset"
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