Newton Fractal

phrontister · 2012-11-24 01:39:28

Ah..........got it!

I had looked at the old posts again and tried to use a-z<0.000000001, but that didn't work although I thought it would. However, your ABS fixed it.

Thanks!

EDIT: I've altered the code I posted.

Last edited by phrontister (2012-11-24 01:50:59)

bobbym · 2012-11-24 01:52:10

Hi;

Does it work better or does it still only get there for the interval you had?

phrontister · 2012-11-24 02:02:45

It's just as fast and gives exactly the same result as my original code, which is accurate to 15 digits only. I don't know how to get more digits than that in LB.

What do you mean by "interval"?

Last edited by phrontister (2012-11-24 02:04:06)

bobbym · 2012-11-24 02:14:31

I wrote an LB program for it, and unless my initial guess is between 33.886745 and 39.999999, LB goes crosseyed.

Must you still enter between those two numbers?

phrontister · 2012-11-24 02:58:58

Hi Bobby,

Yes. If I enter >=40 or <=33.886744, LB gives a Runtime Error.

Btw, the interval isn't precise...it's truncated so it fits into the 'Prompt' window (see image) that opens when starting the program.

Last edited by phrontister (2012-11-24 03:05:10)

bobbym · 2012-11-24 03:05:08

Hi;

SQR(1600-x^2)

This line is causing some of that.

phrontister · 2012-11-24 03:16:52

Do you mean both denominators in that line?

And what about the derivative line?

I might try my code on the polynomial that I posted in the other thread...but maybe the bogus roots might be an issue (just a thought).

phrontister · 2012-11-24 03:18:16

No...I can't try it on the polynomial, because I don't know how to get the derivative.

bobbym · 2012-11-24 03:20:26

Hi;

SQR(1600-x^2)

When x is greater than 40 then x^2 is greater than 1600. So when you subtract something bigger than 1600 from 1600 you get a negative number. LB does not know how to deal with the square root of a negative number.

SQR(1600-x^2)

phrontister · 2012-11-24 03:25:27

Oh, of course. I don't know what to do about that, other than to give the polynomial a try.

That will have to wait until tomorrow, though. I'm off to bed now.

See you later, Bobby.

bobbym · 2012-11-24 03:38:34

Hi;

Okay, see you tomorrow.

Agnishom · 2012-11-24 16:14:01

One question, Do any of you use the POV-Raytracer?

bobbym · 2012-11-24 16:15:40

Hi Agnishom;

I am sorry, I do not?

Agnishom · 2012-11-24 16:19:03

Hmm...Okay..No Problem
I had been thinking to use it to generate Fractals

bobbym · 2012-11-24 16:21:31

There are some nice fractal programs out there. I used to use fractint.

Agnishom · 2012-11-24 16:23:09

Is it free to download?

bobbym · 2012-11-24 16:24:22

I believe it is or at least it used to be.

Agnishom · 2012-11-24 16:59:03

Let me see ...

Agnishom · 2012-11-24 17:05:13

This program is for DOS and I think I won't be able to run it properly

bobbym · 2012-11-24 17:13:22

They have windows versions but they are 16 bit and I can not run them.

Check these out:

http://www.chaospro.de/

http://fractice.sourceforge.net/index.html

http://www.eclectasy.com/Fractal-Explorer/

http://element90.wordpress.com/software/downloads/

http://hsfractal.sourceforge.net/

more-of-a-variety-of-gnarls-s20120117-04-1200x800.jpg?w=1000

Agnishom · 2012-11-25 00:15:44

Wow! these are nice
By the way, I tried hsfractal today morning, and found that it works on my 32bit machine

bobbym · 2012-11-25 00:29:33

Hi;

Very good! Have fun with it.

Agnishom · 2012-11-25 00:44:58

Thanks for the links you provided

Among those, which one is your favorite and which is the second favorite?

bobbym · 2012-11-25 00:52:37

Hi;

I am a little partial to the one that drew those pictures. They are amazing.
The HS fractal is the one I like the least. All the rest I think are better but that is up to
you to decide.

phrontister · 2012-11-25 00:56:31

Hi Bobby,

phrontister wrote:

bobbym wrote:
I wrote an LB program for it, and unless my initial guess is between 33.886745 and 39.999999, LB goes crosseyed.
Must you still enter between those two numbers?
Yes. If I enter >=40 or <=33.886744, LB gives a Runtime Error.

This LB program on RosettaCode.org that finds the roots of a function is different from mine, and asks for a range for x (ie, separate minimum and maximum values).

For the polynomial function no upper and lower limits seem to be required, but the result is a couple of decimal places less accurate and it also finds a bogus root.

I found a derivative online (I didn't know how to do them) for the polynomial, but my LB program hangs for some reason. Debugging revealed a couple of things that I tried to iron out, but to no avail. I'll leave it there, though...I'm losing interest with this one.

Math Is Fun Forum

#26 2012-11-24 01:39:28

Re: Newton Fractal

#27 2012-11-24 01:52:10

Re: Newton Fractal

#28 2012-11-24 02:02:45

Re: Newton Fractal

#29 2012-11-24 02:14:31

Re: Newton Fractal

#30 2012-11-24 02:58:58

Re: Newton Fractal

#31 2012-11-24 03:05:08

Re: Newton Fractal

#32 2012-11-24 03:16:52

Re: Newton Fractal

#33 2012-11-24 03:18:16

Re: Newton Fractal

#34 2012-11-24 03:20:26

Re: Newton Fractal

#35 2012-11-24 03:25:27

Re: Newton Fractal

#36 2012-11-24 03:38:34

Re: Newton Fractal

#37 2012-11-24 16:14:01

Re: Newton Fractal

#38 2012-11-24 16:15:40

Re: Newton Fractal

#39 2012-11-24 16:19:03

Re: Newton Fractal

#40 2012-11-24 16:21:31

Re: Newton Fractal

#41 2012-11-24 16:23:09

Re: Newton Fractal

#42 2012-11-24 16:24:22

Re: Newton Fractal

#43 2012-11-24 16:59:03

Re: Newton Fractal

#44 2012-11-24 17:05:13

Re: Newton Fractal

#45 2012-11-24 17:13:22

Re: Newton Fractal

#46 2012-11-25 00:15:44

Re: Newton Fractal

#47 2012-11-25 00:29:33

Re: Newton Fractal

#48 2012-11-25 00:44:58

Re: Newton Fractal

#49 2012-11-25 00:52:37

Re: Newton Fractal

#50 2012-11-25 00:56:31

Re: Newton Fractal

Board footer