How many numbers exist which are: less than 1000, multiple of 18 and also multiple of 10? Use Maple to find the answer 

Hello everyone! My English is not very good. 

I have writtien Lucas sequence program:

F := proc (n::nonnegint)

option remember;

if n < 2 then n else F(n-1)+F(n-2) 

end if;

end proc;

L := proc (n::nonnegint)

if n = 0 then return 2 end if;

if n = 1 then return 1 end if;

if n <> 0 and n <> 1 then return

L(n-1)+L(n-2) end if; end proc;

S:=proc(n::nonnegint)

 local i;  

for i from 1 by 1 to n do   S(i)=L(i)^(2)-5*F(i)^(2);

 print("%a",S(i));  end proc: 

And Maple notice :error

I don't know call procedure inside another procedure. 
Thank you so much

Regards

sunflower

Hello everyone!

I'd like to as a question that might be very simple, but the thing is that I am completely new to Maple, and I have some homework I need to solve all of a sudden... I tried watching some tutorials and did a lot of search, but I just can't make this one work.
Briefly - my task is to derive the vibrational modal shapes of an annular disk (a circular disk with the center "missing"). So far what I know for sure is, that the radial term of the vibrational deflection is given as a linear combination of 4 types of bessel functions (J_n, Y_n, I_n and K_n) - bessel functions of the 1st and second kind, and modified bessel functions of the 1st and second kind. Something like this:

R_mn(r) = A*J_n(kr) + B*Y_n(kr) + C*I_n(kr) + D*K_n(kr).

Now, I need to find the values for k (the wavenumber), and the coeffitients B, C and D. I don't need coeffitient A, because I'll jus fix that to be 1. To do this, I have the following 4 boundary conditions:

1) R_mn(b) = J_n(kb) + B*Y_n(kb) + C*I_n(kb) + D*K_n(kb) = 0

2) R'_mn(b) = k(J_n'(kb) + B*Y_n'(kb) + C*I_n'(kb) + D*K_n'(kb)) = 0

3) R''_mn(a) = k²(J_n''(ka) + B*Y_n''(ka) + C*I_n''(ka) + D*K_n''(ka)) = 0

4) R'''_mn(a) = k³(J_n'''(ka) + B*Y_n'''(ka) + C*I_n'''(ka) + D*K_n'''(ka)) = 0

So, four equations in four unknowns (k, B, C and D) - and I can't get it to work.

I did the following, and it gives me some totally wrong values (complex wavenumbers and such). Again, I am completely new to Maple, so I might have done something completely silly without even noticing...

b := 0.17e-1;
a := 0.8e-1;
n := 1;

R(r) := BesselJ(n,k r) + B BesselY(n, k r) + C BesselI(n, k r)  + D BesselK(n, k r) ;

eq1 := R(b) = 0;
eq2 := eval(diff(R(x), x), x = b) = 0;
eq3 := eval(diff(R(x), x, x), x = a) = 0;
eq4 := eval(diff(R(x), x, x, x), x = a) = 0;

solve([eq1, eq2, eq3, eq4], [k, B, C, D])

What is it, that I am not doing right?

Thank you very very much for the help in advance!
Andras

Hi everyone,

I am trying to copy a 178x2 matrix into maple. the data is in a .dat file in two columns. For example the first few lines:

+2.000000E-10 +1.636232E-05

+3.017707E-05 +4.531920E-05

+6.065973E-05 +7.586885E-05

+9.096636E-05 +1.059570E-04

+1.208671E-04 +1.357189E-04

I have in mind

.

My unsuccessful trials are

evalf(Int(cos(log(x)/x)/x, x = 0 .. 1, method = _d01akc));

Error, (in evalf/int) NE_QUAD_MAX_SUBDIV:
  The maximum number of subdivisions has
  been reached: max_num_subint = 500

and

evalf(Int(cos(log(x)/x)/x, x = 0 .. 1, method = _d01akc, methodoptions = [maxintervals = 2000]));

Error, (in evalf/int) NE_QUAD_MAX_SUBDIV:
  The maximum number of subdivisions has
  been reached: max_num_subint = 2000

and

evalf(Int(cos(log(x)/x)/x, x = 0 .. 1, method = _d01ajc));

Error, (in evalf/int) NE_QUAD_NO_CONV:
  The integral is probably divergent or slowly convergent.

Mathematica cracks it without any options, producing 0.323367.

restart;

with(DETools, diff_table);

kB := 0.138064852e-22;

R := 287.058;

T := 293;

p := 101325;

rho := 0.1e-2*p/(R*T);

vr := diff_table(v_r(r, z));

vz := diff_table(v_z(r, z));

eq_r := 0 = 0;

eq_p := (vr[z]-vz[r])*vr[] = (vr[]*(vr[r, z]-vz[r, r])+vz[]*(vr[z, z]-vz[z, r]))*r;

eq_z := 0 = 0;

eq_m := r*vr[r]+r*vz[z]+vr[] = 0;

pde := {eq_m, eq_p};

IBC := {v_r(1, z) = 0, v_r(r, 0) = 0, v_z(1, z) = 0, v_z(r, 0) = r^2-1};

sol := pdsolve(pde, IBC, numeric, time = z, range = 0 .. 1);

what am I doing wrong?

it's telling me: Error, (in pdsolve/numeric/par_hyp) Incorrect number of boundary conditions, expected 3, got 2
but i did just as in the example :-/

Hello,

I tried to solve below equation, but it gives me zeros result. Please help me to find their inverse laplace. 

 It will be clearer if was pasted on Maple:

restart

Ps := [P[0], P[1], P[2], P[3], P[4]]:

eqs := [P[0](s) =~ (P[1](s)*mu[1]+P[2](s)*mu[2]+P[3](s)*mu[3]+P[4](s)*mu[4])/(s+lambda[1]+lambda[2]+lambda[3]+lambda[4]), P[1](s) = lambda[1]*P[0](s)/(s+mu[1]), P[2](s) = lambda[2]*P[0](s)/(s+mu[2]), P[3](s) = lambda[3]*P[0](s)/(s+mu[3]), P[4](s) = lambda[4]*P[0](s)/(s+mu[4])];

Ls := solve(eqs, Ps(s))[];

P(t)=~inttrans[invlaplace]~(rhs~(Ls), s, t);

Thank you

Hello everyone!

Prime:= proc (a, b)

local i, p, r;

p := ();

r :=() ;

for i from a to b do

   if isprime(i) then p := p union (i) end if;

     if type(sqrt(p[i]-1), integer) then r := r union (p[i]) end if;

end do

end proc;

Prime(1, 10)

My English is not very good. I don't know what erros I get in my program. Thank everyone

I'm trying to run c code generated from a simple MapleSim example (Spin Up Beam). To makes things even simpler, I set the input real expression to just time, and changed the input function in my c code to:

static void inpfn(double T, double *U)
{
U[0] = T;
}

I set all the state variables to 0 for the initial conditions. I ran the code and my output doesn't resemble the MapleSim output at all, and I'm getting errors. So my question is about the state variables, which I initially set to 0:

* State variable(s):
* x[ 0] = `Main.SpinUpBeam.FB3.uf1`(t)
* x[ 1] = diff(`Main.SpinUpBeam.FB3.uf1`(t),t)
* x[ 2] = `Main.SpinUpBeam.FB3.uf2`(t)
* x[ 3] = diff(`Main.SpinUpBeam.FB3.uf2`(t),t)
* x[ 4] = `Main.SpinUpBeam.FB3.vf1`(t)
* x[ 5] = diff(`Main.SpinUpBeam.FB3.vf1`(t),t)
* x[ 6] = `Main.SpinUpBeam.FB3.vf2`(t)
* x[ 7] = diff(`Main.SpinUpBeam.FB3.vf2`(t),t)

What do these represent for this flexible beam (FB3)? I.e. what is uf1, uf2, vf1, vf2? Should they be set to 0, or no?

Thanks.

I have several *.mw files which I have built seperately. Now, for readability reasons, I would like to create a Master document, which will ues the first files, and then generate a PDF document.
I tried the read command, but it does not recognize the files.

Any help is appreciated.

Let say I want to perform symmetry analysis of ODE, taking into account parameters.
In order to do it I must generate system of determining equations and them to split it for different cases.
But if I use PDETools, actually it gives me only 1 case (worksheet PDETools.mw is attached).
In that case, surely it is very easy to do it by hand and to determine that A=0 and A<>0 are two different cases.

But automatic procedure of PDETools seems to me that somewhere allows to divide by parameter...

Hi

I'm trying to solve this in maple:

solve({0.001=x*exp(0.6/(n*0.026)), 0.01=x*exp(0.68/(n*0.026))},{x,n})

Wolfrom alpha can do it: http://www.wolframalpha.com/input/?i=solve%28%7B0.001%3Dx*exp%280.6%2F%28n*0.026%29%29%2C+0.01%3Dx*exp%280.68%2F%28n*0.026%29%29%7D%2C%7Bx%2Cn%7D%29

Why can't i get maple to do it?

Thanks in advance!

Best regards

Emil

Wonderful.mw

Hi all

I don't know what is its meaning???

The plot and the solved Zero-roots aren't coincident with each other...

Zero-roots: 7.532332868 Wheras from the plot we noticed that there's a root near 14...

And why this Code can't find other Zero-roots?

Thanks a lot

I am trying to manually enter some data into some TimeSeries format and then use that in an Animated BubblePlot but there are few examples.  Can someone create an example to show some random data entered in as a time series so that BubblePlot can animate it?  I am having many problems with this.

please I want a clear explanation for the command (contourplot) in the maple?

contourplot