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maple plotting diagram breaking down

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Jim

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Mar 9, 2003, 2:30:52 PM3/9/03
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Hi,

I am plotting the logistic map fractal along the X/Y axis the
following and seeing that at some point with a slight change to a more
granular picture the whole plotting diagram overflows and displays
nothing..... :

X axis range : 3.8540779627 .. 3.85407796330
Y axis range : .13566 .. .13568

changing the Y axis min to just .13567 blows the diagram.. does anyone
have a clue why this happens or better yet how to fix this problem so
I can get very granular zoomed in views of the logistic map fractal
without the rendering breaking ?

Thanks,

Jim

Alec Mihailovs

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Mar 9, 2003, 2:43:20 PM3/9/03
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"Jim" <jim_fu...@hotmail.com> wrote in message
news:c34e217d.03030...@posting.google.com...

That might happen because of the OpenGL graphics driver. The following plot
setup usually corrects that:

> plotsetup(gdi);

Alec Mihailovs
http://webpages.shepherd.edu/amihailo/


Jim

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Mar 9, 2003, 11:51:58 PM3/9/03
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"Alec Mihailovs" <al...@mihailovs.com> wrote in message news:<sPMaa.7239$aq6.5...@news3.news.adelphia.net>...


Actually, that didnt do the trick...it changed the visual somewhat,
but you can see here what I was describing above...a minor more
granular change from .13567 takes it out of whack...any other ideas ?
Here are the pics:
http://www.pbase.com/jim_fukuyama/inbox

Alec Mihailovs

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Mar 10, 2003, 12:41:15 AM3/10/03
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"Jim" <jim_fu...@hotmail.com> wrote in message
news:c34e217d.03030...@posting.google.com...
> Actually, that didnt do the trick...it changed the visual somewhat,
> but you can see here what I was describing above...a minor more
> granular change from .13567 takes it out of whack...any other ideas ?
> Here are the pics:
> http://www.pbase.com/jim_fukuyama/inbox

It's hard to tell where the problem is without seeing the code. Another
suggestion is to change the number of digits - try something like

> Digits:=14;

or more (but not much more :-)

Alec


Robert Israel

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Mar 10, 2003, 1:01:37 AM3/10/03
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In article <c34e217d.03030...@posting.google.com>,

It's because the rendering engine uses limited precision. A work-around
is to transform the data to more reasonable intervals before plotting,
e.g. with (x,y) -> [10^8*(x-3.8540779627), 10^5*(y- .13566)].

Robert Israel isr...@math.ubc.ca
Department of Mathematics http://www.math.ubc.ca/~israel
University of British Columbia
Vancouver, BC, Canada V6T 1Z2

Alec Mihailovs

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Mar 10, 2003, 1:12:29 AM3/10/03
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I just looked at the pictures in their increased size. It looks as it might
be a typo in the Y range in the second example. Also, it is better to add 0
in front of the decimal dot, such as 0.13566 .. 0.13568 .

Alec


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