The h Bar

Bernardo Meurer

12:00 AM

It's good for systems programming, which is my thing

ArtOfCode

@BernardoMeurer yeah, it is. C# WPF is pretty nice.

Bernardo Meurer

Yeah, I don't own Windows

ArtOfCode

that also doesn't help for C# dev :)

Bernardo Meurer

@ArtOfCode I messed with WPF ages ago

I sed SDL/2 recently, and it's raw, but works well enough

GTK is supposed to be really nice too

I've heard QT can be a bit of a mess

ArtOfCode

Family keep saying "oh, my computer doesn't do <thing I want>, you can make me software for that right?"... so I end up using WPF quite a lot

dmckee

12:02 AM

@BernardoMeurer I agree, but the 'virtual machine' it embodies doesn't map as closely to the real hardware as it did in the '70s and 80s.

0celouvskyopoulo7

@BernardoMeurer idk man

@Slereah and I have had some intense discussions lately

Bernardo Meurer

@dmckee Fair, but I still think everyone should learn C; it teaches you how to think like a computer

And it's not as painful as ASM

@ArtOfCode I never coded anything for my family :/

I'm usualyl engaged in more, ehm, exotic (useless) projects

ArtOfCode

@BernardoMeurer keep it that way

once you write one thing for them, they'll keep asking

I started charging extended family, which cut back a tiny bit, but not immediate family

dmckee

I'm old school enough that I maintain that anyone who can't drive a stick can't drive and anyone who can't at least muddle their way through code using honest-to-goodness, foot-shooting-enabled pointers can't really program.

Bernardo Meurer

Well, I don't even know how to cross-compile for Windows so I guess I'm safe

dmckee

12:05 AM

But I have to admit that the power embodied in modern RAD languages is awesome and I no longer suggest that every programmer should be good at pointers.

Bernardo Meurer

@dmckee Pointers are just confusing

0celouvskyopoulo7

@ArtOfCode People in my family never ask me for my expertise ;_;

ArtOfCode

@dmckee From a slightly more recent perspective, I tend to say that "being able to program" isn't about knowing some technical aspect like pointers really well - it's about knowing your language to a good standard and being able to use it to solve a practical problem

dmckee

Pointers are simple, but you must be painfully pedantic about your bookkeeping to use them safely.

0celouvskyopoulo7

Well my sister did once but it was some obscure statistics thing

ArtOfCode

12:07 AM

@0celouvskyopoulo7 can you tell them to teach my family how to do that?

0celouvskyopoulo7

@ArtOfCode Become a geometric analyst...

Bernardo Meurer

@ArtOfCode If you don't know and understand pointers well you're missing a really big part of programming

0celouvskyopoulo7

Ok programmer people. My LED lamp is flickering. What should I do?

ArtOfCode

I'm currently being roped into developing and hosting some charity's website because my parents are involved in it. I'm looking forward to telling them I'll be charging for it.

dmckee

@0celouvskyopoulo7 Run it from a potato and install linux on it?

ArtOfCode

12:09 AM

@BernardoMeurer Oh, I do get pointers - I just don't think that's the epitome of programming ability indicators

@0celouvskyopoulo7 percussive maintenance

0celouvskyopoulo7

@ArtOfCode You seriously have the audacity to charge your parents?

Jesus Christ, maybe you are 10.

@ArtOfCode I tried hitting it a few times already.

Bernardo Meurer

@0celouvskyopoulo7 Capacitor

ArtOfCode

@0celouvskyopoulo7 for doing some charity's website that I have nothing to do with and they're only vaguely involved in? Yep.

dmckee

@ArtOfCode The epitome is turning the problem inside out so that you can reduce the computational complexity and the code length in one swell foop.

Bernardo Meurer

^

ArtOfCode

12:10 AM

@dmckee Yeah, I'd agree with that

Bernardo Meurer

The epitome is writing self-modifying code

dmckee

But you don't et the chance to do that very often and you can't produce it on demand to show people.

0celouvskyopoulo7

I bought too much spinach and it's going to go bad

dmckee

@0celouvskyopoulo7 That's OK. It's good for your compost heap. Your yard needs iron, too.

ArtOfCode

throw girders at it

0celouvskyopoulo7

12:13 AM

@dmckee What compost heap?

Bernardo Meurer

@0celouvskyopoulo7 Listen to me, just add a goddamn capacitor to the DC out of the PSU, before it reaches the LED

Do you have a voltimeter?

It must be 5V

0celouvskyopoulo7

What would a capacitor do?

It's the LED dying

It's only one of the bulbs doing it

Bernardo Meurer

A capacitor would make the energy flow more constant/reliable

without spikes

(A large enough capacitor)

A flickering LED is generally caused by inconsistent power delivery

IME

sparkfun.com/products/8982

Adding one of these in line should do it

Rated up to 25V

0celouvskyopoulo7

I don't have money for supplies

ArtOfCode

not even 35 cents?

Bernardo Meurer

12:19 AM

It's 35 cents

ArtOfCode

it will invalidate any warranty the lamp has, though

0celouvskyopoulo7

@ArtOfCode It was like $20 and two years old

Bernardo Meurer

Fixing it really isn't hard

You just need to stablize power delivery

HsMjstyMstdn

2:51 AM

Anyone here ?

HsMjstyMstdn

3:06 AM

@0celouvskyopoulo7 could you help me understand something ?

0celouvskyopoulo7

3:26 AM

@HsMjstyMstdn like what

HsMjstyMstdn

Could you "walk" me through the integration of Rotsor's answer here ?

3

Q: Attractive force between capacitor plates

A textbook question requires me to calculate the force of attraction between plates of a parallel-plate capacitor. The answer provided is $\frac{1}{2}QE$. I am not entirely sure how they arrived at it. The charge on each plate will be $Q=CV$ so from Coulomb's law, won't the force be defined as ...

I can't figure out why he takes four integrals and why that square root looks like it is

I mean, I understand he's summing up the two areas of the plates while taking the axes of each plate to be X1 Y1 and X2 Y2 but why is it (x2−x1)2+(y2−y1)2+d2 at the bottom of the fraction ? Is it Pythagoras in 3D ?

Avantgarde

4:42 AM

No one?

Qmechanic

1

Q: When does a 2D metric have a 3D-surface representation?

Certain non-flat, 2D metrics can be visualized as a 3D surface. The metric for the surface of the unit sphere, $$ds^2 = d\theta^2+\sin^2\theta\,d\phi^2,$$ would be the most familiar example. Others are more esoteric: in Martin's General Relativity: A Guide ..., he visualizes the following metri...