🔒 How to make a julia set - beginer

[sonic orbit]

@supple lance

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[hidden robin]

I've never done Julia Sets, but I have done Mandelbrot Sets many times, and they're a similar algorithm afaik.

[supple lance]

idk what afaik means?

[hidden robin]

"as far as I know"

[supple lance]

i was doing mandelbrot sets but it was too hard

i thoguht an easier equations would be easier

[hidden robin]

I don't think they're too different. I think Julia sets are just a generalization of Mandelbort Sets.

[cedar mountain]

it seems as if you meant realNum * (realNum-1) instead of realNum * realNum-1

[hidden robin]

I'll see if I can find some code that shows the algorithm I've used previously.

[supple lance]

honestly i was just watching a video explaining complex numbers and he made some code wich gave out numbers but they were different to mine

so ik mines wrong

idk what im doing

[hidden robin]

Also, Python has a complex number type btw. You don't need to do the complex number math yourself.

[supple lance]

im confused

isnt complex numbers just a number times swrtof -1

[hidden robin]

!e

print(1+2j, type(1+2j))

[sonic orbit]

:white_check_mark: Your 3.12 eval job has completed with return code 0.

(1+2j) <class 'complex'>

[supple lance]

what maths is needed

[hidden robin]

At least with Mandelbrot sets, you square the complex numbers as part of the iteration.

[supple lance]

really? i thought c is the comlex number

u only ever add it?

[hidden robin]

Ah, I was thinking of the limit test. You can square the complex result when checking if the point is going off to infinity.

[supple lance]

is c constant in mandelbrot

?

[formal thunder]

C is how complex number set is usually marked, so small c is sometimes used as "some complex number"
Just like natural number set is N and n is used to mean "some natural number"
We're talking about actual values, not variable names, here.

[hidden robin]

c is the point being tested iirc, so ya, for each point, c remains the same.

[supple lance]

ya

[formal thunder]

Ah, yes, in case of Mandelbrot, the function is defines as f_c (f with lower index c) - it's function f for given c

[supple lance]

what is a value of c that does work

[hidden robin]

It's where the iteration starts at, and it gets added back on to the intermediate result ever iteration.

I don't know why it's set up like that, but those are the rules.

[supple lance]

yea i

ik

is something like this correct

as the mandelbrot set

or nah\

it cant be that easy

[hidden robin]

Here's the last algorithm that I wrote (Rust, not Python unfortunately: https://github.com/carcigenicate/mandelbrot_explorer/blob/d0776e0bab5dc26960672b231411ab9fe01f102c/src/logic/mandelbrot_iteration.rs#L20

[sonic orbit]

src/logic/mandelbrot_iteration.rs line 20

pub fn test_point(initial: ComplexPoint, max_iterations: u32, infinity_limit: u32) -> u32 {```

[supple lance]

i dont really udnerstand

[hidden robin]

Nvm, I'm realizing now that I haven't actually looked at the formal Mandelbrot definition in forever and have just been re-translating my old algorithm every time I redo the project. My algorithm actually seems different than the formal definition. I have no idea where I got it from at this point.

I originally wrote that core algorithm like 10 years ago from some source.

[supple lance]

ok

can anyone explain howe to get this to work

like what ive done wrong

[delicate zodiac]

you would have to check for the modulus for the number "z" after each iteration, and if it is over 2 then "c" is not part of the set.
If after the maxIterations the modulus of z does not go over 2, we consider c to be part of the set

Doing this over different values for "c" will get you the mandlebrot set

[supple lance]

so the mandelbrot set hasincreased resolution with more valeus of c?

[delicate zodiac]

yes, essentially

each c gives you 1 pixel

[supple lance]

and what is a good jump between each value of c

like should i add 0.01to c each time or smth

[delicate zodiac]

yes that seems good

[supple lance]

allrighhty

and then how much iterations for each

[delicate zodiac]

since python is not very quick, something between 25-50 should be good

also you do have to vary the complex component of c as well

[supple lance]

btw wdym by the modulus of z

like u need 2 numbers

[delicate zodiac]

yeah, because c=a+bi(writtten a+bj in python)

[supple lance]

yes but u said modulus of z

thats not possible

like z modulus what

[delicate zodiac]

so modulus here means "distance of complex number from (0, 0) on the complex graph",

[supple lance]

ohh k

[delicate zodiac]

and not "remainder" (ik its kinda confusing)

[supple lance]

wouldnt that just be equal to c

cuzi didnt really include acomplex number

[delicate zodiac]

yeah here it would be the value of the number it self,
but for a general complex number its value would be (a^2 + b^2)^.5 where the number is z=a+bi

[formal thunder]

|z| in math notation
abs in python (handles complex type by default)

[formal thunder]

Just use abs in python

!e print(abs(3+4j))

[sonic orbit]

:white_check_mark: Your 3.12 eval job has completed with return code 0.

5.0

[delicate zodiac]

yeah i was about to write that but u said it first

[supple lance]

how is3+4j 5

[delicate zodiac]

as (3^2 + 4^2)^(0.5) = 25^0.5 = 5

[formal thunder]

abs(3+4j), not 3+4j
Because 3+4j is just 3+4j

[supple lance]

is something like this correct

@formal thunder

[formal thunder]

No. You'd want to iterate each point maxIter times. Not maxIter iterations and going only up with the points

And each point is 2d - each point has real and imaginary part. While your c is just c+0j

[supple lance]

yea if i add the j its breaks

[formal thunder]

It's not "add the j", j character is part of the literal value

[supple lance]

wdym by this

[formal thunder]

Do you know what literal is in programming? It's value that is read, well, literally. String literal is quotes+stuff between the quotes. Int literal is just a number.

Complex literal has either just imaginary part, so it has to be some number and j. Or real+imaginary part.
Like 4+3j above is a literal with real part. Or you'd want to use 1j to convert something to imaginary part (e.g. a*1j).

[supple lance]

i added the j

i really dont understand how i change it to make it work

each time the results do like 1iteration before passing abs2

[formal thunder]

Of course they do, because i is your outer loop. So it will stay being i=1 until all of the inside finishes...

[formal thunder]

I mentioned it here how your loops are opposite

[supple lance]

yea

[supple lance]

both loops are in max iterations times

changing that wont change anything

[formal thunder]

It's about what each variable means (where it's used), not how many times the loop iterates over

[supple lance]

yea

so whats wrong with the variables

[formal thunder]

I wrote it in that message. You'd want to change c in the outer loop, while the inner loop only calculates all z values for the given c

As you yourself said before the code - c is constant for the given z calculation

[supple lance]

then the second loops is repeating the same equation 50 times

should i removeit

[formal thunder]

Why do you think it's the same?

[supple lance]

this code is repeated maxiter times

ohh

[formal thunder]

Does this code also "repeats the same equation 50 times" or not?

x = 2
for i in range(10):
  x = x*x

[supple lance]

shoot uea

nvm

im stupid

watching a stream, doign hw and this at same time

[formal thunder]

You're not. It just sounds like you still lack a lot of basics

[supple lance]

idk

doing this to learn

i feel like i know most of the basics

[formal thunder]

Define "most of the basics"

[supple lance]

like arrays

functions

that kindastuff

[formal thunder]

!d array you mean this? Or list?

[sonic orbit]

array

This module defines an object type which can compactly represent an array of basic values: characters, integers, floating-point numbers. Arrays are sequence types and behave very much like lists, except that the type of objects stored in them is constrained. The type is specified at object creation time by using a type code, which is a single character. The following type codes are defined:

Similar names: numpy.term.array

[supple lance]

like lis

list

[formal thunder]

List is not an array

[supple lance]

ok

very similiar

and i basically meant array

like numpy.array([])

^^^

[formal thunder]

Set? Dict? Classes?
For this here you'd also need to at least understand complex number basics, you didn't even understand how abs works on them nor what j is.

[supple lance]

ik what it is

someone said modulus

then said thats what abs is

when i think it is %

anyway thanks for ur help

im pretty busy this week but maybe next wekend ill try do some more of this stuff

cya

[formal thunder]

Because that IS the alternative name for absolute value. And with complex numbers when modulus is used often, saying "modulus of z" is shorter "absolute value of z"

[supple lance]

ok

[sonic orbit]

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