love maths

love maths

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So if you are given a 3x3 matrix i was just wondering how to use plot3d and plot the 3 column vectors given by it?  Thanks.

So im trying to write a maple script that computes the Jordan form of a given (3x3)- matrix
A. If {a,b,c} is a basis with respect to which A is in Jordan form, then I'm trying to make it
plot the three lines spanned by a, b and c, in the standard coordinate system. I was hinted to use plot3d here.

sidenote: I know how to compute the jordan matrix of A, such by find the eigen vectors and generalised eigen vectors and putting them in as columns in a 3x3 matrix say S,   where S is invertible    then  (S^-1)*(A)*(S) = (J).

Thanks in advance. <3

has anybody any idea for this?  been stuck on it for a while now.

 

let f0 € V be any given function and define a sequence (fn)n€(No) of functions fn € V by 

f:= f0 and fn+1 =Af for all n € (N0)        #A could be the average of the four surrounding points to (i,j) or it could be an N x N matrix with spectral radius less than 1.  not entirely sure. I dont know what it should be but im sure one of you guys know.

prove that this sequence converges pointwise,

 i.e that for all i,j €  [N] x [N], foo(i,j) := limn-> oo fn(i,j) exists.   and that Δfoo=0 

 

it  says to be in the notation of (" http://www.mapleprimes.com/questions/201278-Fix-A-Syntax-Error-In-My-Simple-Function-please-Help")  but it doesnt matter if its not.  I can adapt to what its meant to be if I can get any way to prove it

Thanks in advance.

 

 

okay so we have to, In the Notation of this question http://www.mapleprimes.com/questions/201278-Fix-A-Syntax-Error-In-My-Simple-Function-please-Help , let f0 be contained in V be any given function and de ne
a sequence (fn) with n contained in (N subscript 0) of functions fn contained in V by

(f subscript 0) := f0  and   fn+1=Afn  for all n contained in (N subscript 0).


prove that this sequence converges pointwise, i.e. that for all   i,j contained in [N]X[N],
(f subscript infinity)(i, j) := (lim n-> infinity  fn(i, j)) exists and that "triangle"(f subscript infintiy) =0
and that
f1 = 0 :

any help would be much appreciated guys <3  


firstly apologies in advance for stuff in this question such as "triangle symbol",  my computer is pretty old. 


ok so i was confused a bit here, what i'm trying to do is write a maple procedure that computes Af for a given f contained in V . except we only need to correct the bug in the script below. This script demonstrates such a procedure in the case that omega is a square. The domain is given here as the negative set of a function F contained in V .  I have left in notes where/what i think we need to do but i dunno how to...

N:=10 ; # Global Var
F:=(x,y)->sgn(abs(x-N/2)+abs(y-N/2)-N/4);
Average := proc(F, f0) local f, i, j;
f := f0; # !!!!!!!!!!!!!! something is bad here...
for i to N do for j to N do
if F(i, j) < 0 then
f[i, j] := (f0[i - 1, j] + f0[i + 1, j] + f0[i, j + 1] + f0[i, j - 1])/4 ;
end if;
end do;end do;
return f;
end proc;
f0:=Matrix(N,F); # just to have something to test the procedure
Average(F,f0); # does not return the expected average, modifies f0

 

the necessary information we were given to produce this so far was..

Let N be a positive integer and [N] = {i contained in N | 1<= i <=N }  Let "Omega" C {(i,j) contained in [N] x [N] | 2<=i,j<=N-1} be a subset. Let V = R^([N]x[N]) be the vector space of real valued functions [N]x[N] -> R
and A, "triangle symbol":V->V (average) and "triangle symbole" (Laplacian) be the linear maps such that
[Af](i; j) = f(i; j)      if (i; j) not contained in "Omega"   OR

                             [f(i, j + 1) + f(i, j - 1) + f(i + 1, j) + f(i - 1, j)]/4 if (i,j) is contained in "Omega"

["traingle symbol"f](i,j) =  0 if (i,j) isnt contained in "Omega"   OR

                            ( f(i,j) - [f(i, j + 1) + f(i, j - 1) + f(i + 1, j) + f(i - 1, j)]/4 )    if (i,j) is contained in "Omega"

 Please and thank you for any help in advance <3

                           

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