[lim_x->c f(x) = lim_x->c g(x) in {0, -∞, +∞}]^∃[lim_x->c f'(x)/g'(x)] => lim_x->c f(x)/g(x) = f'(x)/g'(x) is pretty nice. <3
lucas
i ❤ demo -- but cannot edit my profile?
common sense doesn't need a name
True. And I'm extremely sorry. :(
$ xterm -geom 159x100
$ ghci
Prelude> let f = 1 : 1 : zipWith (+) f (tail f) in take 780 f
See anything interesting?
It should work with any language... If you don't have Haskell you could try it in Ruby with
$ irb
irb(main):001:0> def f(n); r = [1,1]; 2.upto(n-1) { |i| r << r[i-1] + r[i-2] }; r; end
irb(main):002:0> f 780
Fibonacci numbers are awesome :)
bsdlite
thinks darkness is his ally
> ^∃
i don't understand the notation at all, bluet; is this a statement of l'hospital's theorem?
lucas
i ❤ demo -- but cannot edit my profile?
It's supposed to be. I attempted to translate Wikipedia's definition with words.
lucas
i ❤ demo -- but cannot edit my profile?
is there an operator that means " has the same sign as " ?
one way to do it is this:
ab > 0 <=> "a and b have the same sign"
but i want a cleaner way that looks like this:
a [operator] b
lucas
i ❤ demo -- but cannot edit my profile?
the fun way to say "ab > 0" is "a and b are on the same side of zero." it makes me smile. :)
I think you could say "a, b > 0".
lucas
i ❤ demo -- but cannot edit my profile?
i think "a, b > 0" means "a > 0, b > 0"
Isn't that what you meant? It's like saying "both are positive".
Oh, I see, "both are negative" should be true too.
I guess for clarity you could use "sgn(a) = sgn(b)" where sgn is the signal function.
sgn x | x < 0 = -1
| x > 0 = 1
| otherwise = 0
lucas
i ❤ demo -- but cannot edit my profile?
:) cool, will do. i might call it "sign()", but "sgn()" is nice because it works for "sign" and "signal."
i used the sign() function in my thesis theory section in order to allow for ordinal ranking of outcomes whose expected value is less than zero:). mu is expected return from an outcome. tao is stochastic standard deviation. mu and gamma are preference parameters.
expected utility = U=sign(mu)|mu|^theta-tao^gamma
how impossible would it be to get code that compiled equations in posts to latex dynamically? just thinking it would be pretty awesome.
lucas
i ❤ demo -- but cannot edit my profile?
probably not extremely difficult
Or you could add MathML support.
lucas
i ❤ demo -- but cannot edit my profile?
yeah, i was looking at that, too.