Axel Vogt

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20 years, 227 days
Munich, Bavaria, Germany

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These are replies submitted by Axel Vogt

Remark aside, just to simplify notations: instead of the factor (k1 + k2) * R one just use one parameter, which now is real (and may be negative, since k1+k2 may be negative).

Fine that DirectSearch finds it

Anyway it seems there exist classical results for that task, http://dlmf.nist.gov/10.21#ix, http://dlmf.nist.gov/10.21.F6.mag

 

It would make sense, if the poster would say what is the name of his pdf. Perhaps it would make sense to check first the literature for answers to his questions.

Do you mean something like this:

NumericEventHandler(invalid_operation = `Heaviside/EventHandler`(value_at_zero = 1/2)):
Heaviside(x);
plot(%, x = -3 .. 3, discont=true, thickness=2, color=red);

 

 

 

limit(x^t, t=0) assuming 0<x;
                                  1
limit(x^t, x=0) assuming 0<t;
                                  0

Writing x^t = exp(ln(x)*t) and using "School Math argumentation" this is:

limit(x^t, t=0) = limit(exp(ln(x)*t), t=0) = exp(ln(x)*0) = exp(0) = 1

limit(x^t, x=0) = limit(exp(ln(x)*t), x=0) = exp(ln(0)*t) =
  = exp( -infinity * t) = exp( -infinity ) = 0

Since it "jumps" there is no common limit for both at the same time,
there is no contious limit as an extension, which would be a natural
definition in (x,t) = (0,0). Thus take any you like.

Yes, because of "infinity". After completing squares for x0 the results are in terms of elliptic functions and depend on cases for sqrt(x0 - I). One can achieve it by integration up to oo, assuming 0 < oo.

Not very friendly, but it will give a way (I guess) - though the solution depends on x0 and its role for the root. And one should feed that / know it in advance.

 

I see the same, but almost never use online help (it does not work properly as soon as some privacy protection is installed).

But within Maple it is fine. And only within Maple you can play with the commands.

In an old thread, http://www.mapleprimes.com/posts/41888-Jordan-Form , there is a link to a paper, which may cover that, and after searching it the paper is available as http://hostel.ufabc.edu.br/~daniel.miranda/wp-content/uploads/jordan-operacional.pdf and some proofs at  http://hostel.ufabc.edu.br/~daniel.miranda/?page_id=845

 

writing m * exp, not mexp, should do it

Thx - I have not tried it (do not want an account) - what is the header /actual content the receiver will see? Can you upload a text file showing it?

I do not consider it as a bug, which is Maple's common notion for a SCR
(is that ITIL compliant?).

But I  have a *change request*: the documentation is too poor, how sad.
And I would prefer to define the (field?) of coefficients in advance,
not in the very command only.

And to have it only over Z or the closure of the field would be a dream.


# http://www.mapleprimes.com/questions/206511-Polynomial-Ideals-Over-Qsqrt2
restart:
with(PolynomialIdeals):
alias(alpha=RootOf(x^2-2));

alpha

(1)

L := <x^2*y^2-2>; # L := <evala(x^2*y^2-2)>;

L := `<,>`(x^2*y^2-2)

(2)

PrimaryDecomposition(L, {alpha});

`<,>`(x*y-alpha), `<,>`(x*y+alpha)

(3)

PrimeDecomposition(L, {alpha});

`<,>`(x*y-alpha), `<,>`(x*y+alpha)

(4)


Download Polynomial-Ideals-Over-Qsqrt2.mw

Polynomial-Ideals-Over-Qsqrt2.mw

 

To drill it down to a simple case: do you want to solve something like 0=diff(f(x), x)+g(x) for f(x) ?

I think you have to solve it numerical.

Maple finds the symbolical values of the integrals (using 'value' as command), but that is in terms of (incomplete) Elliptic functions holding you variables as input. And this way one can not find a symbolix solution for your task.

You can try it evaluating Int(t^4/((t^2 - s^1)^2+y^2)^(1/2),t = 0 .. 1) to see the problem.

By the way: it is likely that there is more than 1 solution (and there might be complex solutions as well9.

The question is not quite clear to me. Can you state what are your unknowns and what are you parameters?

For example f and E are only in the first equation, so the second equation does not matter.

Also note the f/E can by replaced by one variable and solving for that will give you lots of f and E.

For you parameters you may wish to provide restrictions - as far as you know them (like x an Integer, the others are Reals and positive or something like that).

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