« first day (1581 days earlier)      last day (3432 days later) » 

11:00 PM
As I understand, if we are to plot all possible values of $c\mathbf{v}$, we get a straight line, where it's $x$-coordinate spans from negative infinite to positive infinite, and same thing for its $y$-coordinate. I imagine if we are to draw the linear combinations of $\mathbf{v}_1$, $\mathbf{v}_2$, we would get a plane in $R^2$. But imaginations can fail.
 
@SalehenRahman What if $c_1=\alpha\cdot c_2$? ;-)
 
welcome back alizter
 
hi what
 
nothing
just saying hello
 
I was thinking about fractals
then I drew a doodle
now I need a program to write that doodle
 
11:07 PM
:D
 
I'm guessing I don't understand some concepts of linear algebra. I would imagine it should not matter much. Multiplying a vector in $R^2$ by all scalars in $R$ should yield a straight line.

Or am I missing something?
 
doodles are nice
 
@SalehenRahman Imagine that $c_1=\alpha\cdot c_2$. What is $span(c_1)$ ? $span(c_2)$ ?
 
@Hippalectryon are $c_1$ and $c_2$ vectors?
 
@MikeMiller @Alizter Noodles > Doodles
 
11:10 PM
noodles are ok
 
@SalehenRahman I meant $v1,v2$
@MikeMiller What about fractal noodles ?
 
gross
 
@Hippalectryon Ah, now I see where you're going. Both spans represent the same line (I think that's the correct terminology).
 
Indeed @SalehenRahman
 
Hm... I was about to ask the following:

OK, so, then, let $\mathbf{v}_1$, and $\mathbf{v}_2$ be linearly independent, can I safely say that that $\text{span}(\mathbf{v}_1, \mathbf{v}_2)$ equal to $R^2$?

But now I'm thinking that because they are linearly independent, we can find any values $c_1$, $c_2$, such that the equation $(x, y) = c_1\mathbf{v}_1 + c_2\mathbf{v}_2$, holds true.
 
11:19 PM
Indeed
$\mathbb{R}^2=span(v_1,v_2)$ iff they are linearly independant @SalehenRahman
 
@Hippalectryon thanks a lot! :)
 
Good night
 
This article on procedural planet generation is pretty interesting
3
More math-y than I expected it to be but I'm perfectly happy with it being so :)
 
@ZachSaucier Reminds of the the spherical-minecraft terrain generation algorithm
 
11:31 PM
This might sound like a crazy question, but is it possible to extract a basis (or, if many, bases), for a span of vectors, regardless of whether they are linearly independent or not?
 
@SalehenRahman It is !
It's awfully easy from what you say :)
Won't the basis just be your vectors minus the ones that are linear combinations of others ?
 
@Hippalectryon Yeah. I just realized that after taking a quick glimpse at a YouTube video.
 
Can anybody tell me where the 1.28 comes from in problem two? mnstats.morris.umn.edu/introstat/stat2611/exam32001sol/…
 
@David I'd suggest you ask on main, at this hour not many people are in the chat
 
11:41 PM
Thanks.
 
@David I don't know stats, but methinks it's the number of standard deviations away from the mean in which 80% falls.
 
How do I calculate that? So far in the class we've only used the standard normal distribution table, and -.8, .8, $\sqrt{.8}$... none of it comes to 1.28
 
certainly 1.28 is an approximation. I don't know how you go about approximating it either, though I can look that up.
 
Looking for an explanation of the math on this page: http://www.trade.tf/faq
Specifically how to calculate item prices for A,B,C,D. I don't understand where the author got the formula from.
 
@KarlKronenfeld, I just asked a question if you figure it out. Might as well earn some rep if you can.
 

« first day (1581 days earlier)      last day (3432 days later) »