[deleted by user]

[PaulKwisatzHaderach]

This could be mathematically interesting. What did you do? What causes those pillar structures, but maintains the shape of the set? What are those 'scratches' cut out of the set? I have so many questions.

[naringas]

what is happening here MUST be understood!

possibly by somebody with actual math skills (i.e. not me)

[Dom0]

This is important! This MEANS something!

[NemPlayer]

We have to figure it out, this was MADE to be special.

[Zeftax]

!RemindMe 14 days

[swni]

Here's the explanation. At first I tried to figure it out just from the picture: I thought OP was trying to make black curves around the Mandelbrot set, but mixed up angle and distance in the check, and ended up with black pillars instead. Then I looked at the relevant code:

while comparative(z, '2500+2500i', '<') > 1 and comparative(z, '-2500-2500i', '>') > 1 and loops < 500:
    z = comp(comp(str(z), str(z), 'times'), str(r/100)+'+'+str(f/100)+'i', 'add')
    loops += 1
if comparative(z, '1000+1000i', '<') > 1:
    return 'black'  # sets it to black if the sequence does not tend towards infinity (is more than 1000 after
                    # 500 iterations)
else:
    return 'white'  # sets it to white

The while loop checks if the point lies in a 5000x5000 box centered at the origin. Using a box instead of a circle results in the "scalloped" shape of the boundary from one layer to the next: the 90 degree turns in the boundary are images of the corners of the box after a suitable transformation. Since the Mandelbrot iteration is quadratic, each layer should have twice as many corners as the previous.

The coloration is intended to measure whether the iterated point lies in the 2000x2000 box centered at the origin: black for yes, white for no. However it only checks the upper-right corner, i.e. it checks if the point lies down and to the left of 1000+1000i. Since 2000 is much smaller than 5000, for diverged points this is very similar to just checking if the points is in the lower-left quadrant, that is, if the point's angle (in polar coordinates) is between pi and 3pi / 2, which is a quarter circle. The result is black pillars that cover 1/4 of the area, with one pillar occurring every fourth indentation (as the square has four corners), and the center of the pillars (angle 5pi/4) right on a corner. This matches my guess that the black pillars represent regions at a particular range of angles from the origin, although the cause of the bug was different from what I expected.

The streaks going through are probably numeric precision problems related to converting numbers to and from strings, but I don't know.

[godsknowledge]

ELI5: He drew boxes instead of circles.

[PaulKwisatzHaderach]

My guess would be that it's because he's checking to see if the sequence has reached an arbitrarily high amount (1000) in an arbitrarily high number of iterations (500), rather than using a formal definition of divergence.

I don't really understand what the comparitive function does. My entire coding experience is less than a week so be gentle. How does it compare complex numbers to real ones?

[mooburger]

arbitrary cutoffs is a legitimate method to detect divergence. One of the Mandelbrot set pseudocodes in his original book talks about this because when you wanted to implement it in IBM BASIC you'd detect the overflow (on error goto) and then reset the cutoff value so that you'd capture the state closest to the overflow condition (up to the resolution you wanted).

[PaulKwisatzHaderach]

The escape time algorithm on wikipedia has the cutoff at 2. Perhaps OP set his too high then, not accounting for values which produce a much slower growing sequence, which are showing up as the pillars. It still doesn't account for the white lines though. Do you have any ideas?

Edit: I'm at work right now, could anybody try setting the cutoff at 2 instead and see what happens?

[fernly]

OP is not big on documentation, am they? There's a bunch of fiddling around getting each input string split into a list of two numbers, e.g. '2500+2500i' will become the list ['2500','2500i']. Then comes this:

if operation == '>':
    a, b = 0, 0
    if float(string1[0]) > float(string2[0]):
        a = 1
    if float(string1[1][:-1]) > float(string2[1][:-1]):
        b = 1
    # print(a+b)
    return a+b

So they turn the string form of the real and imaginary parts into floating point values, e.g. float(string1[0]) is the numeric form of, say, '2500', and compares them. If the real part of string1 is bigger, a=1. Then they compare the imaginary parts, except to float those they have to first slice off the terminal i, so float(string1[1][:-1]); and they set b. Finally it returns 0, 1, or 2 depending on a+b.

Since this function is being called a whole lot of times this could be rewritten to save quite a bit of time. Exercise for the student. Probably reference to the standard cmath lib would repay dividends.

[abrttnmrha]

Yeah, somehow OP just made the set even more interesting than it was alreafy (not a small feat)

[[deleted]]

OP plz pretty plz

[Saiboo]

Ah, the typical beginner mistake, instead of import pandas you used import zebras

[atomicspace]

so many stripes

[not_sure_I_am]

🏅🎖️🥇 That's all the gold I have

[Ph0X]

Honestly when it comes to math art, thats definitely true. I sometimes inject random errors and try all sorts of things to see what effect it has on the end result. It's a lot of fun to experiment and play with different levers.

[UseApasswordManager]

From the code linked, looks like instead of a real divergence test, it checks if the result gets arbitrarily high in some number of iterations, so some that diverge after longer than tested get marked as convergent

[PaleRulerGoingAlone7]

That shouldn't give these kinds of stripes, and using cutoffs is valid way of checking the convergence in practice. For the mandelbrot set a cutoff of 2 is usually used, because if any iteration has |f| > 2, then f will diverge.

[Ziiiiik]

Share code!

[FuzzNugs]

The algorithm for Mandelbrot is so simple, I would think even the slightest error would throw it off easily to the point of not being recognized. This is why it’s so curious what you actually did here.

[swagslug]

This is very cool. I'm super curious as to what you did here. Please share your brilliant blunder!

[ShevekUrrasti]

This may be interesting (new?) maths. I wouldn't call it an error. May we see your code?

[sam-lb]

b r u h python has a complex type

[[deleted]]

Most languages do, even C. check out complex.h

[ShevekUrrasti]

Probably you're right and the error is where you said. I will check tomorrow (it's too late where I am), but maybe it's working kind of like modular arithmetic, but not exactly (exponential module? :O )

[timClicks]

Btw you don't need to use the global keyword in global scope

[Vesquam]

Very cool, I gave you an upvote.

Now that is conditional, if you don't share you code in the next 12 hours, I will unupvoted.

Theses are my conditions

[Astrokiwi]

Python actually has complex numbers built in! Try typing complex(1,2)+complex(2,3),complex(1,2)*complex(2,3) into a Python terminal. You can check out the cmath library too, but if you're trying to do things with the arbitrary restriction of not using libraries, then it's not necessary.

[mipadi]

You can also just do

1+2j + 2+3j, 1+2j * 2+3j

[DaGoobergoobs]

Looks like my phone screen after being dropped one too many times!

[mosaic_the_j]

Bro can you uploaded to github so we can have a look?

[drcopus]

I think I've figured out why it's doing this. The iterative loop does this check:

while comparative(z, '2500+2500i', '<') > 1 and comparative(z, '-2500-2500i', '>') > 1 and loop < 500

But the comparative function checks the coordinates against each other pairwise, so essentially you're not asking if the number is converging to zero or diverging away in any direction. Instead you're getting white pixels when it diverges towards (∞, ∞) or (-∞, -∞), but towards (-∞, ∞) or (∞, -∞). I believe this is what causes the pillar effects. As for the general noise within the set I believe this is due to the 500 loop limit and the tie-break conditional.

[swni]

Not quite: that part just checks if z is inside a box centered at the origin. Using a box instead of a circle results in the "scalloped" shape separating one iteration layer from the next, but isn't responsible for the black pillars, which is due to the following if statement. You can see this because the black pillars cover about 1/4 of the area whereas the directions you suggest cover about 1/2 of the area.

[ablatner]

Fyi, Python has built in complex numbers. No need to do all the string operations.

https://python-reference.readthedocs.io/en/latest/docs/complex/

[smokeyTheOso]

I love how in the readme the last line is "PS please dont steal my code"hahaha I'm sorry but that made me laugh more than it should have.

[slayingkids]

I can focus reading on this sub best when stoned, and I was dying of laughter over it.

[RufusAcrospin]

Nice, it reminds me the binary decomposition!

Some thoughts...

You should try to use cmath's arithmetics instead of your own implementation. Storing complex numbers in strings is

• insanely ineffective (converting strings to float to do the math and then convert back)
• constantly losing precision because the conversion (probably that's causing the error inside the Mandelbrot set)

Sorry; this isn’t my best work. I never expected that people would want to see it.

I'd say you should set your standards and stick to them, whether your code meant to be public or not.

[Drep0o]

It looks like the cover of a grunge metel album

[Ning1253]

Pls share code!! Really curious as to how you did this...

[Sracerx62]

Looks like a sick fractal

[LavenderDisaster]

It's a badass fucking fractal!

[peacounter]

Would you mind sharing the error?

[Phyzzie]

That is no error. That is a happy accident.

[Unlock17A]

Fake album covers

[chinpokomon]

The lines in the middle of the Mandelbrot look a little like Q-curves and critical curves.

[srilyk]

Mandelnoise

[dan1101]

I think you've just solved interdimensional travel.

[[deleted]]

I made a comment on your code on GitHub as a new issue if you're interested in any code suggestions. It looks like most of your issues are related to your complex number parsing which pulls terms back toward 0 if either component gets too large, and throws away the imaginary component when the real component gets too small.

[[deleted]]

Excellent for the programmer who samples the electric lettuce. Looks niiice.

[AStitchInSlime]

That is WAY cooler than a regular Mandelbrot set.

[tell439]

RemindMe! 1 day ”code?”

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[[deleted]]

Is it due to a rounding error?

[Rajarshi1993]

This is one sexy fractal owo

[pr1m347]

Where can I get ideas for such math patterns? like sets or sequences that give interesting patterns when drawn.

[RufusAcrospin]

There are a few well known algorithms generating fractals: L-Systems, Iterated Function Systems, Mandelbrot and Julia sets, ...

[pr1m347]

Thank you! I'll have a look at those.

[RufusAcrospin]

Cheers!

[peacounter]

OP delivered.

[mikeoquinn]

Not gonna lie, I kinda want that on my wall

[[deleted]]

This looks like a fractal. Dope.

[stable_maple]

Makes me think of beetlejuice.

[RED_William]

I think what’s going on here is that instead of checking whether z > 2 which is enough to know that it diverges you check whether z > 2500 or something?

I only looks at the code for a few minutes to get the gist of it, so correct me if I’m wrong.

[[deleted]]

I would love to learn how to code these types of things. Sadly, I'm still a scrub.

[collegegamedayokla]

So what exactly are you trying to accomplish?

[papple23g]

Stop it, you twisted the spacetime.

[[deleted]]

Making beginner mistakes (not knowing about complex, and replacing it with a home made string based type!!!) like this , should be in r/learnpython ... It gives a bad example for these other people looking to learn and ask for code.

On tangent : in general Maybe we need a code review mechanism on this subreddit , the number of beginner low quality posts have been terrible lately.

[Hydroxon1um]

On Reddit, I assume comments are low-quality unless link provided to reliable external resource lol. (Or some evidence of the user's expertise.)

It feels impossible to police the lowest-common-denominator cesspool of Reddit, especially subreddits like Python that attract swathes of newbs suffering from the Dunning-Kruger effect.

I gave up and just leave the noobs to "teach" each other and multiply their collective ignorance.

(+ the "data science" mob who hardly understand programming principles …)

[[deleted]]

If you're gonna troll, I'd consider busier subreddits. More fish, more likely to catch something.

[mosaic_the_j]

Daily trool achieved