The h Bar

AccidentalFourierTransform

Maple locks down their site licenses more than Mathematica does

why this new obsession with libre shit?

who cares

It's Libre

Because you are all being abused by corporate shills and their proprietary malware

shills

AccidentalFourierTransform

And you must choose freedom

12:23 AM

I like being abused

although shrills was funny

i'm mostly libre or whatever

stallman.org/saint.html

There is no system but GNU, and Linux is one of its kernels!

@heather You still have shackles to break young one

AccidentalFourierTransform

and its other kernels are barely functional!

kbye

12:25 AM

@BenNiehoff Not true, GNU Hurd is perfectly working

@Bernardo such as...?

@AccidentalFourierTransform May your dreams be blessed by GNU

@heather DRM, Codecs

I do notice you said perfectly working, not working perfectly ;)

@BenNiehoff You caught me there :P

@Bernardo what are those...?

12:26 AM

GNU HURD: working as designed!

but actually, I love free software and even ran Arch Linux on a laptop for a while

@heather Non-free software

MP3 for example is a non-free codec

Don't use it

use FLAC, OGG, Opus

@BenNiehoff It is so wonderful, although their microkernel is far from the linux and it is also a little bit... big.

@BenNiehoff I use Arch, but do note it's not Free Software. There is an Arch Linux analogue that is free software called Parabola

but I don't use it much anymore, because I use a Surface Pro 4 and Linux just doesn't agree with it

@BenNiehoff I think, hurd would be the best if it would use a very mutilated Linux as microkernel.

12:31 AM

oh, ok, then I don't care about Free Software, only free software ;)

The Linux kernel is just a mess nowadays

@BenNiehoff For example, it the case of the USB drivers, I can't see any reason why they should be in kernel space. Communicating on an usb channel is exactly like communicating on a TCP socket. The same is for the filesystem, they are essentially demons providing a dav-like directory API using a block device.

Microkernels are the future, but they're just that; the future

there is one thing that I can't stand about the FOSS movement, though

and I think it's a result of removing money, and thus customers, from the equation

That is indeed a problem

12:35 AM

a lot of developers get arrogant and leave bugs unfixed and features unimplemented, by saying that the user shouldn't want those things

@BernardoMeurer The Linux modules should be userspace daemons. It wouldn't be very hard to make them working from user space. It shouldn't be the future, it should be real in the present.

@peterh Yeah, well, I don't know about that (how hard it would be)

oh, the other thing I can't stand is people focusing way too much on the elegance of the design, even on the language it's written in, rather than the end-user experience and whether it does what someone needs

@BenNiehoff Elegance of the design has a direct impact on the user experience

like I don't give a shit whether it's written in Fortran or cuneiform, but does it work?

12:38 AM

@BernardoMeurer All of the drivers see an interface on which they are talking with the rest of the kernel, partially with other modules. They call eachother by call instructions. These call instructions should be changed to some IPC mechanism. Even source modifications wouldn't be needed.

@BernardoMeurer To a degree, yes, of course. But it's not something to obsess over.

@peterh I mean, I know how drivers work, but I also know that many of them are hackish as hell and easy to break

And, "we never break userspace"

You can't future-proof anything, ever

@BenNiehoff Hm, I disagree, I think it's the one thing to obsess over. A good design will stand the test of time

and save you from refactoring everything every 6 months

but it all gets refactored every 6 months anyway :P

because FOSS is a developer's hobby

12:41 AM

Meh, it's not necessarily a hobby

I know plenty of people who work in FOSS

Heck I've worked in FOSS

yes, I know people get paid to do it

@BernardoMeurer Yes, the bad drivers wouldn't work.

@BernardoMeurer I've just compiled a latest 4.10.4 kernel with make allnoconfig, the result is an 570kB bzImage. It would be a good start for a new microkernel.

when I call it a hobby, I mean that the focus is usually on the developing

it's fun to design and write software!

@peterh I just think if you're going to go through the trouble of making a microkernel just make it a new design

it's a bit less fun to do good research on what the user wants or needs, and good testing to make sure everything works well

12:46 AM

make it POSIX and it should still be compatible with Linux for the most part

1:11 AM

@BernardoMeurer I just spent 1.5 hours explaining measure theory to bob

@BenNiehoff I know of a German book that uses tetrad. I don't really understand the logic there :P

@AccidentalFourierTransform You've never seen a good proof in a class that you've never seen anywhere else?

@0celo7 I need to meet bob

1:30 AM

hi @bernard @0celo7

@Obliv hey man! You're back!

Just in time for the post-mortum of my CPU

what have we learned?

lol what happened

omg

DO NOT, I repeat, DO NOT, write to the wrong memory buffers in loop while walking through the addresses

obliv sup

dmckee

1:32 AM

@BernardoMeurer Programming close to the metal always allows you to shoot yourself in the foot. The closer to the metal the larger the caliber.

whats up @obe lookin blue like usual i see

dmckee

FPGA are the metal. You figure it out.

@Obliv, hello, how've you been?

I've been good, how about u @heather

pretty good.

1:33 AM

@obliv how did your transfering work out? are you applying this year or did you apply already?

@dmckee So it's like turning my foot into a bazooka and shooting while standing?

dmckee

Yep.

@Obliv hey

@obe no

@bernard do you know much about charles babbage's difference engine? like how he could mechanically approximate differential equations?

@0celo7 whats up dude anything insane happen while i was gone

@0celo7 do you still have your super detailed tensor answer?

i forget if you posted it

the one where you explained tensors properly

1:39 AM

@Obliv All I know about Babbage's contraption was:
1. It never worked
2. The plans were perfect though
3. His notation is absolutely nuts and we're still trying to make heads and tails of it
4. With today's machining precision we could build a working Difference Engine

@Obliv I got married

@OBE no, it was too long

Why?

I want to read it

dropbox link?

or did you delete it

@bernard we already have two in the world I thought.

It's in a series of .tex files on my hard drive

It's not something I care to put together

I encourage specific, intelligent questions.

okay whenever you have time if you could link it it would be helpful

since i couldn't appreciate it back then

but i can appreciate it more now

1:43 AM

I know that he used the idea of finite differences of polynomial approx of differential equations but I can't figure out how he mechanically designed this.. I figure it's similar to the differential analyzer (which is wayyy simpler) but Im too curious..

just look at it..

@OBE just ask questions

how could that thing possibly determine finite differences using $f_{k+1} = (1+h)f_k$ and outputting the result in a result column

Tensors are pretty easy, what do you want to know

I just wanted to learn them properly

I only know carroll level tensors

and idk which book to use

brb

There's only one book

1:50 AM

back which book?

link

@OBE there's only one book.

@OBE I'm very disappointed

wait

not hawking and ellis

is that what you're referencing?

No

phew

i remember looking at that and thinking it was crazy (hard)

@heather did you understand my proof earlier

2:02 AM

sort of

i have to go to bed now

good night everyone

o/

anyone have an institutional login at this (website)[ieeexplore.ieee.org/document/1498720/]

i forgot how to embed links in text LOL it's been too long

@Obliv Apparently I do

square brackets and round brackets go the other way round for links in text

:O could you share this document with me pretty please @artofCode

ah okay thought it was something like that

@Obliv ping me an email at hello@artofcode.co.uk, I'll send it back to you

this is illegal

please stop discussing in chat

2:17 AM

...that was the point of the whole email thing

@0celo7 flag me

(don't actually, because i know you will)

2:59 AM

@ArtOfCode I don't see any difference between this an planning a murder

I don't think that would be allowed in the chat

3:18 AM

@ArtOfCode Shoo, go away

Unless you can help me with VHDL

otherwise, shoo

Is $A\cdot B + \overline{A}\cdot\overline{B} = A\bigoplus B$?

Hm

nope

Screw this class really

What is that

@BernardoMeurer uh... Why?

@0celo7 Boolean algebra

@ArtOfCode 'Cause you're mean

@ArtOfCode you have a bad habit of banning people

^

3:24 AM

Not unless they're doing something ban worthy

No such thing

^

Which nobody was, until I was pinged out of the blue at 3:30AM by someone telling me to go away.

@ArtOfCode Do you happen to speak Portuguese?

@BernardoMeurer Wonder if Fantano will like Rozay's new album

3:25 AM

@BernardoMeurer Spanish.

Same thing.

If so I will forgive your sins if you help me with my Computer Architecture lab project

i don't suppose it happens to be the same one I've just done?

Probably unlikely, but hey

fenix.tecnico.ulisboa.pt/downloadFile/1970943312289270/…

Boolean logic I can do, if that helps

3:27 AM

Page 3, question 2

Boolean algebra I can do too :P

I just don't get what he's asking me to change in my CPU design

@BernardoMeurer Apparently Birdman tried to take out Khaled

Didn't work

It's some black magic for doing arithmetic with numbers that use up to 8 bits of the 16 available bits

@0celo7 What?

@BernardoMeurer watch DJ akademiks

Like...everything

@BernardoMeurer yeah, I can read most of those words, but the ing as a whole makes no sense to me.

@ArtOfCode "ing"?

3:30 AM

thing

Ah

Yes, to me neither

I have no clue what he's asking

shrug

Like, I think I get what he's asking

but it seems pointless

He wants me to add something in my ALU that detects when a number is "small" and we define small as >=8bits on the 16 bit bus

in this case we activate a signal small_num and replace all it's 8 signal bits to 0 (two's complement is used here)

we then do the ops normally and flip the 8 bits back if needed

now why I dunno

Eating Weird Food from the 50s (with Katherine)

5:28 AM

42 is the answer to life, the universe and everything. The following might be one tiny slice of that question

user228700

6:51 AM

@JohnR: I have done you a great injustice by not sharing this video with you:

user228700

►

user228700

Enjoy!

John Rennie

:-) I'm a little tied up with recalcitrant servers at the moment, but I will watch it later. British food in the 50s was notoriously bad!!!

user228700

:-) Wokay. Have fun fixing them servers!

7:18 AM

Time is what nature use to prevent everything to happen all at once
Money and price are really means to control and regulate the distribution of resources

If you managed to control both, you control everything in a civillisation
https://en.wikipedia.org/wiki/PyMOL

Why is that? Because infnite cardinals don't physically exist and resources are finite

9:06 AM

So this paper defines a class of loops for timelike curve, but it also includes "stings", which are sort of path wangs sticking out of the form $f \ast f^{-1}$, $f(0) = x$

And you can insert stings on timelike curves by $g \to g_+ f f^{-1} g_-$

But nowhere does he really say really why we need stings

some vague thing about needing them to complete the group structure of the loop space, but then again every curve is $\approx$ a curve without any stings, and also the constant curve $f(\lambda) = x$ is also in the space of generalized timelike loops

So I don't have a clue why you'd need them

Leonhard Euler

10:11 AM

Hello @JohnRennie

Naming yourself after a famous scientist is a bit conceited

Leonhard Euler

Why do you think so?

just an opinion :p

Leonhard Euler

10:36 AM

Oh. But I don't think so

10:58 AM

Here is why integrals are hard. In general, they have no nice infinite series representations:

\begin{align}
I_1(0,x,n)=\int a^{(0)}(x)e^{-nx}dx & = a(x)\left(\int e^{-nx} dx\right)-a'(x)\left(\iint e^{-nx} d^2x\right)+a''(x)\left(\iiint e^{-nx} d^3x\right)-+a'''(x)\left(\iiiint e^{-nx} d^4x\right)+\cdots +(-1)^{R+1}\int a^{(R+1)}(x)\left(e^{-nx}\right)^{(-(R+2))}dx\\
& =\sum_{k=0}^{R}(-1)^ka^{(k)}(x)\left(e^{-nx}\right)^{(-(k+1))} +(-1)^{R+1}\int a^{(R+1)}(x)\left(-\frac{1}{n}\right)^{R+2}e^{-nx}dx\\
& =\sum_{k=0}^{R}(-1)^ka^{(k)}(x)\left(-\frac{1}{n}\right)^{k+1}e^{-nx} -\int a^{(R+1)}(x)\left(\frac{1}{n^{R+2}}\right)e^{-nx}dx\\

NB feel free to let $R,S \to \infty$. Then that final term has to go to zero else the integral will diverge as you will be effectively summing countable number of constants

Also this 'formula' only works if $a(x) \in \mathcal{C}^{\infty}$, otherwise anywhere there is cusp in the kth derivative it will be undefined at those points

As long these conditions are met, then the "indefinite Laplace transform" has a infinite series representation as the exponential function times a series of derivatives of $a(x)$

That is, given some $a(x)$ that satisfy the above conditions, then:

$\int a(x)e^{-x}dx=-e^{-x}\sum_{k=0}^{\infty}a^{(k)}(x)$

11:32 AM

General form of any exponential integrands with bounded derivatives $i.e. a^{(k)}(x)< \infty, \forall k \in \Bbb{N}$, and $n > 1$

$$\int a(x)e^{-nx}dx=-e^{-nx}\sum_{k=0}^{\infty}\frac{a^{(k)}(x)}{n^{k+1}}$$

12:11 PM

christ

too many integrals

Treatingin integrals and sums as linear functionals does make them less headache because it turns an analysis problem into an abstract algebra problem, which I am slightly more comfortable at

but anyway...

12:50 PM

@0celo7 any clue why someone would need those stings

cf this and below

4 hours ago, by Slereah

So this paper defines a class of loops for timelike curve, but it also includes "stings", which are sort of path wangs sticking out of the form $f \ast f^{-1}$, $f(0) = x$