Dear all
I am using Physics[Vectors] package of Maple 17. I want to define an orthogonal curvilinear coordinates through alpha and beta independent variables. To define unit vectors of alpha and beta, I have to apply the derivatives of position vector r_ with respect to alpha and beta, respectively. Please help me to define the unit vectors in directions alpha and beta as derivatives of position vector r_ with respect to alpha and beta, respectively. Please see the below Code:

> restart;

> with(Physics[Vectors]);

> Setup(mathematicalnotation=true);

> r_:=X(alpha,beta)*_i+Y(alpha,beta)*_j+Z(alpha,beta)*_k;

The unit vectors in directions alpha and beta should be defined as:

_alpha=diff(r_,alpha)
_beta=diff(r_,beta)

It is worthwhile to mention that the following expression governs:

> diff(r_,alpha).diff(r_,beta)=0;

Please guide me.

Best wishes

Ali

Могу ли я использовать Клен, чтобы найти конкретные решения, которые выражаются либо в начальных и эллиптических функций для систем обыкновенных дифференциальных уравнений. Например, вы можете получить в Maple решений (sub_Solve01, sub_Solve02) для систем, которые перечислены в файле?
exp01.mw

integral.mw

Hi all, I want the best for you.

I really have confused with this bad integral (HeunB)which I've got it 2 weeks ago from a solution by Maple 17. I should solve this one to solve the derivative of this too.

Help me please, I attached the attribute file.

Regards.

Hi, 

i have this:

and i don't want the letter to be strings.

I want something like:

[z,d,i,p,s,...,y]

Thank you a lot

There was a command for torusknot(x,y,z),r,R.  Is it included in Maple 17? The index and help to do not list it.

Is there a newer version of a torus knot?

Dear,

I have this code generating a piecewise function:

> with(CurveFitting);

> points := [[0, 1], [1, 2.5], [3, 2.3], [4.2, 5], [5, 3.5], [5.8, 4.2], [7, 7], [8, 10]];

> splcurve := Spline(points, v);

In this particular case I have seven distinct polynomials. Someone knows how could I get one specific polynomial, for example, the one exactly before v < 4.2? 

In other terms:

I'd like to define a new function, say 'f', that is exactly the polynomial just before v < 4.2 (e.g, something like f:=(splcurve, v < 4.2)). Do exists this possibility? (I have been looking for it elsewhere but without success!!)

Thanks in advance! Best regards!

****** My question *****

for k from 0 to n do    # n is any integer.

func := f(x):             # func is any funciton of x.

D := diff(func, x$k);   # The maple don't allow to uses k but I want to diff k-th order in each k-loop.

end do;                    # How to diff func for k-th times in each k-loop.

Hi, I'm a big noob in Maple, so may be the answer is very simple.

Thank you!!!

Download black.mw

Not sure exactly how i could achieve this but:

how do i determine the value of k for which the graphs p(x) = x^2+2x+3 and q(x) = k+5x-7x^2 enclose an area of exactly 36?

I have to do it in maple and using i guess area under the curve.

Thanks

Hi there,

I'm trying to get the values from the output of a dsolve command.

I have a system of differential equations:

de1 := diff(V(t), t) = V(t)-(1/3)*V(t)^3-W(t)+Ie;
de2 := diff(W(t), t) = 0.8e-1*(V(t)+.7-.8*W(t))

For a range of the independent variable t and for some given values of the parameter Ie, I would like to get the value of the dependent variable V, as well as its minimum/maximum values for each Ie.

Can anybody suggest a solution please?

This is the worksheet: MaplePrimes_dsolve_min-max.mw

Thanks,

jon

How can I link the axes in two or more separate plots so that when I zoom in one, the others are also zoomed. Also when I want to link the 'x' or the 'y' axis only.

Thank you

Dear mapleprimes users,

I have a problem with this function:

B is the length of my array

A := Array(1..B,0);

for i from 1 to B do
p = nextprime(i)

a = primroot(p)

A[i] := A[i] + convert((Usage(mlog(b,a,p,method=indcalc), output=[cputime,output],quiet)[1],decimal,15))
end do;

A;

My idea is to create an array A with all the CPUtimes from the 1st prime til the Bth prime, and then plot it.

But my problem is that I get an error; Illegal use of an object as a name.

I don`t know what to do could you help me?

Thanks!

How can this error be corrected '' error, (in fsolve) fsolve cannot solve on 0=0 ''. See the worksheet p4.mw

Thanks.

Hi there,

I've been trying to find an equivalent to MATLAB's unique command in Maple, but I had no success.

I've seen that Maple would return the elements that are either repeated (FindRepetitions) or not repeated (MakeUnique), but not the indices within the original list.

Is there way to do that?

Thanks,

jon