Axel Vogt

5821 Reputation

20 Badges

20 years, 227 days
Munich, Bavaria, Germany

MaplePrimes Activity


These are replies submitted by Axel Vogt

Staff seems to be too busy for an answer, yes? Thx anyway.

One needs to allow ajax.googleapis.com (good that GG knows the footprints then) and bootstrapcdn.com

As others already said: much of space on screen is wasted/unsused. A simple button for the 'righthanded side' would correct that. A usual screen 9*16 should lower pleasure, I suppose.

For me the loading hangs up after the initial post ... what is the system trying to load while showing "Ajax-loader.gif" ?

I had to use a completely unprotected browser to see something and to post.

Then probably I do not understand your question. Since cos is periodic
it is enough to have a solutions for cos(z) = a in the period, located
wherever you want it.

And within the period you have a symmetry (this is the 'boolean' variable
in Thomas' answer). So actually one solution is enough (which is what you
observe in your initial formulation).

For z real you need abs(a) <= 1. If you want -oo < a < + oo you can do
as well, but may want -Pi  <= Re(z) <= +Pi (or shifted). And similar for
an arbitrary complex value of a.

Your equation is linear, the result is psi[4](t) = someThing + arccos( ...), depening on various constants and functions, which depend on a variable t.

So what would you expect any system or person to suggest as solution regarding your constraints?

It 'smells' a bit like a bivariate normal with correlation and moments, so I doubt you can do it symbolically (you may wish to write 1/1000 instead of 1e-3, may be you want 0 anyway?).

The best you can do is to explain the task, its origin

@TomM I think your reasoning is not correct:

Matrix(2,2, [f(a)+c1,b,g(c)+c2,d]):
LinearAlgebra:-Determinant(%);
                    d f(a) - b g(c) - b c2 + d c1

So you would need a cancellation condition.

IIRC det and evaluation function commutes, so det( eval(Matrix, sigma=0) ) gives the constant term (*). As Carl pointed out the 'best' way is to use map(convert, Matrix, rational, exact).

(*) For that case you do not need det, you can use "Rank(sigma=0)". And for that I get rank = 6, so det(sigma=0) can not be zero, hence const term is not zero

PS: I used your latest matrix example.

I guess you talk about a Mac (mine is Windows) and perhaps a nordic (?) language. If it is so: a friend once gave me a Word document, the name had an "Umlaut", it was ä. Though it was properly displayed in the GUI I was not able to handle it the usual way. At the command line I saw that this letter was coded by 2 letters, an a and then the two signs above it. After changing the name it worked. So a first step might be to rename using ASCII code only only (and no blanks etc)

switch to 'exact' numerics to avoid round off:

data_deg_ex:=map(convert, data_deg_ex, rational);
Det_data_deg_ex := Determinant(data_deg_ex);

gives degree = 8, lowest degree = 4 (using Digits=15)
and use evalf again on that. Is that ok?

Canceling the obvious common factor it is just 

#t^(1/n-1)*(1-t)^(n-1/n-1) = t^(1/n-1);
#% / t^(1/n-1);

  (1-t)^(n-1/n-1) = 1;               # after canceling, integrands
  map(ln, %)  assuming 1<n, 0<t,t<1; # 'quadratic' equation
  solve({%, 1<n}, n);                # or pick manually from the two

                                 1/2
                                5
                           {n = ---- + 1/2}
                                 2

or let 'solve' do the work (without manually mapping log), using assumptions

Or more simply try the following, confirming vv's answer

product(mu^x[i],i = 1 .. n+1); 
simplify(%) assuming n::posint;
combine(%) assuming n::posint;

@acer It seems that IntegrationTools:-Split(%, 0) for the integral already numerically does it quickly without choosing a method.

Then one can plot the curve directly (without restricting to some points) in a quick way:

f := x -> exp(-x^2):
g := (x,a) -> 1/(1+abs(x-a)):
Int(f(x)*g(x,a),x=-infinity..a-1);
IntegrationTools:-Split(%, 0);
plot(%, a=-1 .. 50);

I guess you mean it is slow with very lenthy output. But what do you expect?

Doing it for smaller order one can guess that an "alias" (---> help) for the constant term can shorten the display.

As a quick solution for me (?) it would be enough to have a filter giving only posts with reputation greater 0.

For example adding that to the menu bar as "Recent +" or similar.

@Markiyan Hirnyk The last sentence is insulting. No need at all for such.

http://www.maplesoft.com/support/help/Maple/view.aspx?path=operators/elementwise&term=Element-wise%20Operators

In the Help system you just type in ~ into the search field and get according topics.

PS: personally I prefer "map", for me usually it is more easy to understand (but your cited example is much more compact code)

 

First 25 26 27 28 29 30 31 Last Page 27 of 207