Ridiculous Notation and Conventions

ITT: Notations or conventions in math and science that make you REEE. Bonus points if we're too far gone to change it and just have to deal with ut at this point.

I know these things are abritrary and don't affect anything drastically, and I know this is a brainlet tier shitpost, but I'm interested in seeing what you all think of this.

> The charge of an electron being denoted as negative, leading to "positive charge flow" in circuits and other retardation.

> The use of π rather than τ. Seriously, what the fuck is this?

> 99% of the notation in differential geometry. Standardise that shit already.

> Δ as the Laplacian. It already has a meaning that is very likely to show up in the same context of applied mathematics REEEEEEE

That's pretty much it for me. What about you autists?

Other urls found in this thread:

khanacademy.org/math/algebra2/manipulating-functions/combining-functions/v/product-of-functions
youtu.be/7zI5zsPuRVs?t=1h21m46s
twitter.com/SFWRedditImages

same

Oh, and the use of "It can be clearly seen" or "It is fairly obvious" in any textbook ever. It's the laziest cop out WRYYYYYY

>REEE
gb2/r9k/ you fucking autistic cancer.

> 99% of the notation in differential geometry. Standardise that shit already.
go and complete your doctorate by doing so.

none of what you mentioned pisses me off as much as putting a space after greentext arrows

>The official name of our moon is "The Moon"
>The official name of our sun is "The Sun"

keke

>99% of the notation in differential geometry. Standardise that shit already.

What isn't standard?

>sin^2(x)=sin(x)*sin(x)

>sin^-1(x)=arcsin(x)

In my experience, every author picks a notation they find most convenient. Which is totally fine, but a bit disorganized.

>this

I always write asine or acos, fuck that negative exponent B.S

Writing the formulas of conic sections not in standard form. Like really, why make me do some completing the square/factoring bs?

>^-1 being the inverse or the reciprocal

Agreed. It looks like bad math. If ^-1 was used consistently, sin^-1(x) should be csc(x)

Anything that is called normal, regular, or prefect in math. We need more Grothendieck's naming shit.

I've seen texts where sin^-1(x) is asin and sin(x)^-1 is csc(x)

I see many authors in biological literature alternate between cytoplasmic and cytosolic as though they're equivalent but they're really not.

Molality is a fucking stupid unit.

And this isn't a notation really but lack of one - nobody respects the capitalization of SI units. I see ml everywhere when it should properly be mL. And fucking using u instead of [math]\mu[/math].

And before you ask why it matters - what is mm? is it millimolar, or millimeter? what about mg? milligram or milligauss? Yes, of-fucking-course it's always obvious from the context what you're talking about, but the point of units is that they should be an unambiguous notation. If you have to resort to inferences from context to figure out exactly what the unit is, the nomenclature is fucked.

You are both retards. I bet you write f^2(x) to mean f(x)*f(x).

Technically it's Sol for our sun, hence Solar system and star system for all the other systems.

d/dx

gay as fuck

> The charge of an electron being denoted as negative, leading to "positive charge flow" in circuits and other retardation.

Electricity does not work the way you think it works.

>He doesn't use Yuler notation
[eqn]D(ie)[/eqn]

I hate grading partial fraction problems because kids don't factor by powers of x and solve with a matrix

People who use one letter in different fonts for different objects which are related to each other, e.g. [math]A,\mathfrak{A},\mathcal{A}[/math]

Anything in modern type theory, get your fucking shit together and stop using all kinds of triangles in your statements and ten different enviroments, all in different cases and fonts.

People using more than two '

>but that's what sin^2(x) means user

TRIVIAL
R
I
V
I
A
L

It's a function. It should adhere to the established notation for functions.

Ah, yeah I misread you before. Yeah the sensible thing would be sin(x)^2 and asin(x) = sin^-1(x) but meh...

The direction of the electric current is defined in the direction in which a positive charge would flow, not in the direction the electrons actually move.

When the CO2 cannisters are empty, doctors in the pharmacology building where I work will stick a note on it for the janitors, but they all write "MT" instead of "empty." I asked about it, and two confirmed that that is what it means. Drives me crazy.

BEDMAS

I'm shocked at how many people confuse or think that multiplication comes after division and that kind of thing. Apparently in Europe, they might do it a bit differently than Americans and Canadians, though I haven't verified that.

Why the hell do addition and subtraction come before multiplication and division anyway? Did some autistic "intellectuals" just suddenly decide that that is the how it should be or is there an actual reasoning that can be demonstrated in the real world?

sin^2 is sin*sin
sin^2(x) is (sin*sin)(x) = sin(x)*sin(x)

why not just sin(x)^2 = sin(x)*sin(x) =/= sin(x^2)
Sin^2 notation may just be a lazy way of drawing less parenthesis but it creates confusion as it appears as an operation applied to an operation. I dislike it.

sin(x)^2 is ambiguous. are you talking about sin((x)^2) or (sin(x))^2?

it's not a lazy way to draw less parentheses. functions form a ring with well-defined sum and product.

You can't really be this stupid. Tell me you're joking.

But everybody writes sin(x^2) if that's what they mean.

That's retarded and also wrong. You can't multiply two functions, you can only compose them.

>f(x)^2 is ambiguous. are you talking about f((x)^2) or (f(x))^2?
This is you. This is what you sound like.

It's useless once you understand what all the notation of standard operations actually means.

You can multiply functions when you get past babby-tier math.

You can only multiply functions evaluated at a value and even then only of the image has a multiplication defined on it.

here's the lowest level example i could possible find

khanacademy.org/math/algebra2/manipulating-functions/combining-functions/v/product-of-functions

They're pretty understandable/concise when you're used to it, but lots of notations/symbols used in standard QFT gets pretty wild.
>Dirac delta
>kronecker delta
>functional derivative
>variation in a function
>delta as a variable itself
>implicit indices on virtually symbol you write down, typically several kinds of contractions implied by juxtaposition of symbols.

Are you retarded?

Do you understand that division is defined in terms of multiplication? You can do them in any order because multiplication is associative.

[math]\frac{a}{b} \equiv a \cdot b^{-1}[/math]

Have you ever heard of the distributive law?

[math]a \cdot (b +c) = ab +ac[/math]

If you want to have precedence order to save your hand from writing parens, distribution pretty much makes the choice of operation order obvious.

When you rely on stupid mnemonics to understand rather than just plain ole understanding, you tend to show your lack of understanding. Understand?

Of course you can multiply functions. You sound sad that composition and multiplication are two different things. Why?

Composition:
[math]f(g(x)) = h(x)[/math]

Multiplication:
[math]f(x) \cdot g(y) = h(x,y)[/math]

You are literally retarded.

When you have f:A->B,
f is a function
f(x) is a function evaluated at x (it is an element in the image of the function.

(f*g)(x) is syntactic sugar for f(x)*g(x). You are never multiplying the functions themselves, only elements in their images. Furthermore, it only makes sense when there exists a multiplication in the codomain and both functions share the same codomain.

For instance I can have continuous functions between topological spaces without algebraic structure (no addition or multiplication).
f:A->B
g:C->D
Then what the fuck is f*g?
What the fuck is f(a)*g(c)??

There is a different notion called a categorical product but in the context of category theory exponents always refer to composition and inverse.

he's dug himself into a semantic hole after getting irrational upset at the idea of sin^2(x) popping up all over the place in virtually every field of science and existing as a well-understood/agree-upon notation.
I wouldn't worry too much, friend.

i never said multiplication between any two functions is always defined

it is still multiplication of functions

you are attempting to be a pedantic brainlet and failing

No it's not. Multiplication of functions would give you a new function. Multiplication of elements in the image is just that.

Suppose
f:A->B
g:A->B
h:C->D

Then fill in the question marks
f*g:?->?
f*h:?->?

You are using a lot of big fancy words there, bob.

Tell that to /b/. When it comes to math, some of those guys are fucking retarded.

when you multiply, for example, polynomial functions, you get a new polynomial function

When people use "~" to mean "is proportional to" and "is approximately". My prof in statistical thermodynamics used to do that and it drove me nuts. Especially since there are alternate notations you can use for both that can't be misinterpreted.

>polynomial functions over a ring
You are multiplying elements in the ring, not the functions themselves.

let's multiply elements in the ring since you insist the functions themselves cannot be. let h(x) = (f*g)(x). what is h? why are you incapable of admitting that there exist cases in which f*g = h?

I can't stop laughing at this image.
Fuck. The rate that Veeky Forums generates shit like this never ceases to impress.

I do that.

More generally f^{-1} for inverse function. But I can't recall another notation

>(f*g)(x) is syntactic sugar for f(x)*g(x).

Disagree. The first is a function evaluated at x, the other is the product of two functions evaluated at x.

(fg)'(x) is not syntactic sugar for f'(x) g(x) + f(x) g'(x)

...

but electrons are negative

>it is fairly obvious that the sky is blue
REEEEE COP OUT

lol moron

lol moron

yeah I don't know why this one in particular is making me giggle like a highschool girl

I'm completely comfortable with this notation but it really doesn't make any god damn sense.

The whole imperial system.

You are a special kind of stupid. Do you know what you get when you take f(x)*g(x) for all x? It defines a function, which we call f*g.

>biochem
>thousands of common names used instead of systematic names

It makes sense for complex molecules, but why can't we just call pyrovate 2-oxopropanoic acid?

Also, acetic acid should be called ethanoic acid.

fuck don't even get me started on qft bullshit

>The charge of an electron being denoted as negative, leading to "positive charge flow" in circuits and other retardation.
Babby can't tell left from right, how cute.

It's really easy to identify the similarities and differences between the conics and their components (foci, vertices, etc.) when you write them in their respective, easily identifiable forms. I'd rather really understand the relationship between a hyperbola's directrices with respect to it's centre than memorise a bunch of "the conic is a hyperbola if A>0, C0, B=0. the conic is a parabola if..."

a big part of notations and names in topology

nah no one calls it ethanoic acid except for high school nerds trying to sound smart. go look at any paper in an org chem journal and you'll see it called acetic acid, and its salts acetates

I never said it's not called acetic acid. Better learn to fucking read, brot.
Using systematic names for simple molecules would make everything easier.

Fuck you, you said "acetic acid should be called ethanoic acid", which is stupid because everyone already calls it acetic acid and knows what that means. Similarly for pyruvate and many other molecules with common names. Everyone's going to look at you funny if you say "2-hydroxypropanoic acid", but everyone knows what "lactic acid" is. It's just easier to use common names for all but the simplest molecules. Dumb cunt.

>2-oxopropanoic acid
>willingly using IUPAC
>even once
kek

im going to cum on all the neps

fuck you fucker fucking cancerous fuck

testing to see if wordfilter ignores caps

senpai
Senpai
fAm
faM
FAm
FaM
fAM
SENPAI

random text at the end to avoid spam filter detection

alright time to attempt to fool the wordfilter

SMΗ TΒH FΑM

How come nobody has brought up mathematical notation? Z and Q for example, let alone all the bullshit like pic related. It should just be called Autism notation. It has nothing to do with math, and everything to do with Autism.

The misuse of e.g. mibi vs mega for computer systems is frustrating. At tibibytes, 1 terabyte is only .93 tibibytes.

The million different syntaxes for programming are beyond the scope of this post.

Mol and Meter are SI units, there's no distinguishing even with caps.

And electrical movement was defined before electrons were. Electrons are negative by being opposed to positive (default) fields. The reasoning is backwards.

We should be more frustrated with anode and cathode.

meter is supposed to be lowercase m, molarity is supposed to be uppercase M. the official SI symbol for mole is "mol", no abbreviation.

It's all quite unambiguous.

more tests:

senpai
senpai
cucks
cucks

>some

>clopen

yeah I'm not sure why people are confused over M, m, mol, and mol dm^-3. you'd have to be real dumb to have trouble over this

>supposed to be
You realize the poster got pissy because "Liter" should have a capital L right? It's retarded and nonsensical to have one of the "prime" units, the "Liter", be capitalized, but "meter", not. Rename it the Mol if you want it to be capital, otherwise stop making up even more nonsensical naming schemes.

It's Euler you retard.

That is also syntactic sugar. In any higher mathematics fg always refers to function composition but it's too hard for babby-math people who use ' for derivative.

>let h(x) = f(x)*g(x)
fixed

This is hardly function multiplication in any sense. All of your functions must have the same domain and codomain and the codomain must have a multiplication for this to even make sense. In this special case you could claim you're defining a multiplication between functions but you're really only doing anything in the codomain.

The definition falls apart as soon as you start changing the domain, codomain, or allowing the codomain to have less structure (i.e. if your functions are just continuous functions from one topology to another, each lacking any algebraic structure).

f and g are sets of order pairs. In particular if [math]f\colon A\to B[/math] then math]f\subseteq A\times B[/math]. When you write f(x) as a polynomial you're evaluating f for arbitrary x. Functions in general are not nearly this well defined (unless you're just working in babby-math).

jesus just fuck off already

BRA-KET notation in quantum mechnaics. I bet they invented it becouse it would be too simple without it.

You do realize and are the same person, right?

Me. I'm that person. Those are my posts.

Actually, the name "Solar system" uses "solar" as an adjective, just like "solar wind" and "solar panels". If you lived by another star, you could call your star system "the solar system" and you would use "solar panels", not "Kepler panels" for example.

I'm not just saying this because of the "Solar system" part. The IAU officially accepted "The Sun" (capital S), "The Moon" (capital M), and "The Earth" (capital E) as the names for these three celestial bodies, until the aliens tell us what they named them.

I find the mispronunciation of "giga" to be even more frustrating.

But mathematical notation is not as autistic if you understand what it says. The propositions stated there are core axioms that define our arithmetical system. The kinds of proofs like your picture are the ways we connect logic to math, so there is a lot of notation that must be used. When you run out of Greek, Arabic, and Hebrew letters and numbers, I think it's better to create new notation rather than new symbols. Every new symbol you create has to have a typographical index, which just makes it even worse to actually write down.

Check out youtu.be/7zI5zsPuRVs?t=1h21m46s , Schuller destroys the notion of bra-ket notation. Skip to 1:36:10 if you get the general gist of the notation and want to hear him really demolish the idea.

>tfw I'm still constrained to using bra-ket notation because of convention and because I work with physicists who have never rigorously proved anything in their life

this

looking at the riemann curvature tensor makes me want to die

looking at diff geo proofs using coordinates makes me want to die

status: SO TOLD

There are cases when index notation reduces complexity of the expressions (in the technical sense). Just objects and concatenations of each other makes some stackings not possible and then you must introduce additional operations to get the same thing that an index summation does.

Z is Zahlen, i.e. numbers. Where's the problem?
Ring is also a German word, which besides "ring" as in "wedding ring" also denotes a group ("Verbrecherring"). So it's like "group".

In electrical and computer engineering, [math]\sqrt{-1} = j[/math].

I know that I is taken but why the fuck did we decide to use it for current?