Freya is a really good programming maths communicator so it doesn't surprise me
this post was submitted on 16 Jul 2023
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wow I wish we learned this kind of stuff in school
Invented in the 50s, Fortran = FORmula Translating language. It was basically created to solve this sort of problem.
I don't know her, so maybe my question is stupid, but does she explain math without using code? I, honestly, am too stupid to programing, I don't understand it. I understand summary, not the second one
I don't know anything about the original post author, but product notation is the same as summation notation except that instead of adding each new term to the running total, you're multiplying each new term. You don't have to know programming to see from the code samples that the only difference in the code is += vs *= (well, maybe it would help to know that * means multiply; I honestly dont rember how common-knowledge that is).
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i still don't understand but thanks
The biggest difference (other than the existence of infinity) is that the upper limit is inclusive in summation notation and exclusive in for loops. Threw me for a loop (hah) for a while.
i thought this was pretty weird too when i found out about it. i’m not entirely sure why it’s done this way but i think it has to do with conventions on where to start indexing. most programming languages start their indexing at 0 while much of the time in math the indexing starts at 1, so i=0 to n-1 becomes i=1 to n.
My abstract math professor showed us that sometimes it's useful to count natural numbers from 1 instead of 0, like in one problem we did concerning the relation Q on A = N × N defined by (m,n)Q(p,q) iff m/n = p/q. I don't hate counting natural numbers from 1 anymore because of how commonly this sort of thing comes up in non-computer math contexts.
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Wouldn't reducer be more precise?
I think this is pretty much the imperative equivalent of foldl (\acc i -> acc + 3*i) 0 [1..4].
Can you explain this out a bit more? I'm a self-taught programmer, of sorts, and I'm not quite getting this...
A reducer “reduces” a list of values to one value with some function by applying it to 2 values at the time.
For instance if you reduce the list [1, 2, 3] with the sum function you get (1 + (2 + 3)) = 6.
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freya is not a random internet people