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Student Support Forum: 'bug in Series[] function' topicStudent Support Forum > General > "bug in Series[] function"

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Author Comment/Response
yehuda
06/06/13 09:50am

I do not see an error here.
You have fallen into the trap of numerical accuracy near critical points...

The denominator of T[z] approaches 0 for z->1/3 so the whole expression is ComplexInfinity
So what would you expect?
With
T[x]-S[x] you first tray to calculate each function (numerically) and then take the difference
Try
Simplify[T[x]-S[x]]
you will get an identical zero

try also T[1/4]-S[1/4]
again zero
trying T[0.333] etc. is calculating T[x] for a point which is near the root but with a fixed accuracy
if you calculate T[0.3333333333333333] you will get a (much) higher value since it is closer to the root

try increasing the precision (say 100 digits )
T[0.333333`100] - S[0.333333`100]

you will get a number which is quite close to zero



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Subject (listing for 'bug in Series[] function')
Author Date Posted
bug in Series[] function Eric Freden 06/03/13 2:31pm
Re: bug in Series[] function yehuda 06/06/13 09:50am
Re: Re: bug in Series[] function Eric Freden 06/06/13 11:44am
Re: Re: Re: bug in Series[] function Forum Modera... 06/07/13 4:59pm
Re: Re: Re: Re: bug in Series[] function Forum Modera... 06/10/13 2:11pm
Re: Re: Re: bug in Series[] function yehuda 06/08/13 2:22pm
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