The Numberphile Topic -- The Official Nerdy Math Topic! [OLD]

math
nobullying

#337

Is this like an espace room!?
I've done one of those before, it's awesome!
You solved mini puzzles and find hidden messages :smile:


#338

Eh, it's kind of like an escape room. Can I post some of the puzzles here? Some of it is math, others are reading, etc.etc.etc.

Edit: It is awesome. :wink:


#339

Sure! Sounds great!
You can probably do that in the Math Questions topic! :grinning:


#340

Okay then. I'll go over there.


#341

Oh haha, I see it now, that's a good one. XD


#342

Why use imperative loops and not recursion? It makes things a lot easier, and without side effects, for example this in python:

def Exponent(m, n):
    if(n==0):
        return 1
    else:
        return m*Exponent(m,n-1)

#343

Yes! I've seen that, it's very helpful
Have you heard of tetration before?


#344

I haven't. Is there anything that goes beyond tetration?


#345

Yes! It goes infinitely far
(Sorta uses Latin roots)
I posted a link about it above, I'll try and find it


#346

Huuuuuge numbers though. I don't see why anyone would need them XD


#347

Hehe I have a problem that is super easy,

So if a kilogram of twiggy sticks are $15.00 and I buy four of them and it costs $1.29 How many grams is approximately each one? How many can I get for a kilogram


#348

I have an issue with tangent. I am not experienced with tan and arctan (inverted tan), but I decided to try this: make a project that counts the angle between two points. I found this math formula online. It will count the angle between two points:
deltaX= Object 2 x - Object 1 x
deltaY=Object 2 y - Object 1 y
Angle in degrees=arctan(deltaY / deltaX) * 180/PI.
This is what I have been thinking:

  1. Hopscotch does the calculation in the wrong order.
  2. I am completely wrong.

Here is my code:


Note: I have the same code for deltaY as I have for deltaX, but using the Y values instead.
And here is the result:

But it does almost work sometimes, like this time:

So, what do you think? I know that you can do this with sin and cos but I don't know how. And, you can make this easy using atan2, but is there any way that you can get it in HS?


TBSr's General Hopscotch Coding Topic
#349

Okay, it's just your last line of code when setting the value of angle that is wrong. Do EXACTLY what the pictures say. (Sorry for being late)


#350

Thank you so much! I will try that!


#351

Wait sorry I made a mistake. The y position should be divided by the x position.


#352

I know I already asked this question before, but I didn't get quite the answer I wanted. Can anyone explain what a 4-dimensional and up hyper plane is? Sorry if you can't answer.


#353

@William04GamerA

The multiplication by 180/PI is not needed. Some programming languages calculate trig functions in radians, which this formula assumes as multiplying by 180/PI is a conversion from radians to degrees. There are 2PI radians in 360 degrees, which simplifies to PI radians in 180 degrees.

The other issue is that formula only works for angles between -90 and +90 deg. Otherwise you have to subtract 180 deg from the result to get the right answer. Angles between -90 and +90 deg are when object 2 is to the right (greater x position) of object 1, so the subtraction of 180 deg can be done when necessary with a If then else block. You mentioned the function atan2. That logic and subtraction is what atan2 does.

This project shows you the code in Hopscotch. It's not too complicated


#354

Is it possible that this topic could help me code momentum relative to portals? They are supposed to conserve momentum.


#355

What even is this. I don't see any math?


#356

What do you mean, you don't see any math? It's a math question. About 4-d graphing?

Edit: Or what are you talking about? It doesn't say which of my posts you replied to. Sorry.