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hai everyone. i am currently trying to solve an integration of the following ∫g(η)dη . integrate from 0 to 10.

from the following odes.

f ''' +1-(f ')2 +ff ''=0,

g''-gf'+fg'=0,

with boundary conditions f(0)=0, f'(0)=λ, f'(∞)=1, g(0)=1,g(∞)=0

First, i solve the odes using the shooting method. then i used the trapezoidal rule to solve for the integration of g(eta) using the following codes

> with(student);
> trapezoid(g(eta), eta = 0 .. 10, 10);
> evalf(%);

it seems that it can not read the data from the shooting method. can anyone suggest why it is happening?

thank you verymuch for your concern :)

Hi

I need a command for adding screentip to maple textbox.When user select textbox field, a comment appear and guide him to write correct format of algebric expression, e.g. when user writes 2sin(x) the format scanner can't specify 2 from 2sin, and user must write 2*sin(x) instead of 2sin(x).

I want explain these hints with screentip.

 

Hello every one.

I want to do some tensor computations in maple in a specified coordinate system but I don't know how! As an example I ask the follwing question.

Consider a second order symmetric tensor "A". I want to compute the components of "curl(curl(A))" in cylinderical coordinates. How should I do this in maple?

This is related to a famous equation in elasticity known as "small strain compatibility" equation.

Thanks for the help

Hi

I am trying to implement the following basis functions $h_n(t)$. Please suggest how to implement. thanks

 

Hello i want to solve the differentiel equation but i have these problem i don't understund  why !?

drive.mw

restart

ode1 := (K[Q]*T*R[a]/K[kol]+R[a]*B[m]*sqrt(T/K[kol]))/K[i]+K[b]*sqrt(T/K[kol]) = 0

(K[Q]*T*R[a]/K[kol]+R[a]*B[m]*(T/K[kol])^(1/2))/K[i]+K[b]*(T/K[kol])^(1/2) = 0

(1)

ode2 := (1/2)*(-(4*(diff(theta(t), t)+theta(t)))*M+2*B1*(diff(theta(t), t)+theta(t))-2*w[2]*sin(theta(t))+m1*g*sin(theta(t))*l[kol]-2*B1*theta(t)+2*w[1]*sin(theta(t))-2*m1*g*sin(theta(t))*l[2])/l[1]

(1/2)*(-4*(diff(theta(t), t)+theta(t))*M+2*B1*(diff(theta(t), t)+theta(t))-2*w[2]*sin(theta(t))+m1*g*sin(theta(t))*l[kol]-2*B1*theta(t)+2*w[1]*sin(theta(t))-2*m1*g*sin(theta(t))*l[2])/l[1]

(2)

 

ode3 := subs(T = (1/2)*(-(4*(diff(theta(t), t)+theta(t)))*M+2*B1*(diff(theta(t), t)+theta(t))-2*w[2]*sin(theta(t))+m1*g*sin(theta(t))*l[kol]-2*B1*theta(t)+2*w[1]*sin(theta(t))-2*m1*g*sin(theta(t))*l[2])/l[1], ode1)

((1/2)*K[Q]*(-4*(diff(theta(t), t)+theta(t))*M+2*B1*(diff(theta(t), t)+theta(t))-2*w[2]*sin(theta(t))+m1*g*sin(theta(t))*l[kol]-2*B1*theta(t)+2*w[1]*sin(theta(t))-2*m1*g*sin(theta(t))*l[2])*R[a]/(l[1]*K[kol])+(1/2)*R[a]*B[m]*2^(1/2)*((-4*(diff(theta(t), t)+theta(t))*M+2*B1*(diff(theta(t), t)+theta(t))-2*w[2]*sin(theta(t))+m1*g*sin(theta(t))*l[kol]-2*B1*theta(t)+2*w[1]*sin(theta(t))-2*m1*g*sin(theta(t))*l[2])/(l[1]*K[kol]))^(1/2))/K[i]+(1/2)*K[b]*2^(1/2)*((-4*(diff(theta(t), t)+theta(t))*M+2*B1*(diff(theta(t), t)+theta(t))-2*w[2]*sin(theta(t))+m1*g*sin(theta(t))*l[kol]-2*B1*theta(t)+2*w[1]*sin(theta(t))-2*m1*g*sin(theta(t))*l[2])/(l[1]*K[kol]))^(1/2) = 0

(3)

simplify(ode3)

(1/2)*(-4*R[a]*K[Q]*M*(diff(theta(t), t))-4*R[a]*K[Q]*M*theta(t)+2*R[a]*K[Q]*B1*(diff(theta(t), t))-2*R[a]*K[Q]*w[2]*sin(theta(t))+R[a]*K[Q]*m1*g*sin(theta(t))*l[kol]+2*R[a]*K[Q]*w[1]*sin(theta(t))-2*R[a]*K[Q]*m1*g*sin(theta(t))*l[2]+R[a]*B[m]*2^(1/2)*((-4*M*(diff(theta(t), t))-4*M*theta(t)+2*B1*(diff(theta(t), t))-2*w[2]*sin(theta(t))+m1*g*sin(theta(t))*l[kol]+2*w[1]*sin(theta(t))-2*m1*g*sin(theta(t))*l[2])/(l[1]*K[kol]))^(1/2)*l[1]*K[kol]+K[b]*2^(1/2)*((-4*M*(diff(theta(t), t))-4*M*theta(t)+2*B1*(diff(theta(t), t))-2*w[2]*sin(theta(t))+m1*g*sin(theta(t))*l[kol]+2*w[1]*sin(theta(t))-2*m1*g*sin(theta(t))*l[2])/(l[1]*K[kol]))^(1/2)*l[1]*K[kol]*K[i])/(l[1]*K[kol]*K[i]) = 0

(4)

eol := (1/2)*(-4*R[a]*K[Q]*M*(diff(theta(t), t))-4*R[a]*K[Q]*M*theta(t)+2*R[a]*K[Q]*B1*(diff(theta(t), t))-2*R[a]*K[Q]*w[2]*sin(theta(t))+R[a]*K[Q]*m1*g*sin(theta(t))*l[kol]+2*R[a]*K[Q]*w[1]*sin(theta(t))-2*R[a]*K[Q]*m1*g*sin(theta(t))*l[2]+R[a]*B[m]*sqrt(2)*sqrt((-4*M*(diff(theta(t), t))-4*M*theta(t)+2*B1*(diff(theta(t), t))-2*w[2]*sin(theta(t))+m1*g*sin(theta(t))*l[kol]+2*w[1]*sin(theta(t))-2*m1*g*sin(theta(t))*l[2])/(l[1]*K[kol]))*l[1]*K[kol]+K[b]*sqrt(2)*sqrt((-4*M*(diff(theta(t), t))-4*M*theta(t)+2*B1*(diff(theta(t), t))-2*w[2]*sin(theta(t))+m1*g*sin(theta(t))*l[kol]+2*w[1]*sin(theta(t))-2*m1*g*sin(theta(t))*l[2])/(l[1]*K[kol]))*l[1]*K[kol]*K[i])/(l[1]*K[kol]*K[i])

 

(5)

R[a] := 1.42;

1.42

(6)

K[b] := 0.649e-2;

0.649e-2

(7)

K[i] := 0.649e-2

0.649e-2

(8)

K[Q] := 0.1051618298e-6

0.1051618298e-6

(9)

l[kol] := 1

1

(10)

l[1] := .7

.7

(11)

l[2] := .3

.3

(12)

K[kol] := 0.1168464776e-5

0.1168464776e-5

(13)

B1 := 0.955e-3

0.955e-3

(14)

B[m] := 0.955e-3

0.955e-3

(15)

J := 0.475e-6

0.475e-6

(16)

M := 0.91e-2

0.91e-2

(17)

m1 := 0.726e-1

0.726e-1

(18)

w[1] := 0.72e-1

0.72e-1

(19)

w[2] := .45

.45

(20)

g := 9.81

9.81

(21)

a1 := 0

0

(22)

eol

-.4851223862*(diff(theta(t), t))-.5119876735*theta(t)-6.626549550*sin(theta(t))+.1077211171*2^(1/2)*(-42167.66273*(diff(theta(t), t))-44502.83918*theta(t)-575990.9557*sin(theta(t)))^(1/2)

(23)

simplify(eol)

-.4851223862*(diff(theta(t), t))-.5119876735*theta(t)-6.626549550*sin(theta(t))+0.1523406647e-3*(-0.4216766273e11*(diff(theta(t), t))-0.4450283918e11*theta(t)-0.5759909557e12*sin(theta(t)))^(1/2)

(24)

with(plots)

ic1 := theta(0) = a1

theta(0) = 0

(25)

``

dsol1 := dsolve({eol, ic1}, numeric, output = listprocedure, range = 0 .. 10)

Error, (in DEtools/convertsys) unable to convert to an explicit first-order system

 

plots[odeplot](dsol1, [t, theta(t)], 0 .. 10)

Error, (in plots/odeplot) input is not a valid dsolve/numeric solution

 

``


thanks for your help

Download drive.mw



Is it possible to define and use an abstract linear operator L which is a function of y(x) and z(x)? 

For example, Maple should be able to recognise that L(y(x),z(x)) = L(z(x),y(x)) and simplify expressions such as 

L(c*y(x),d*z(x)) = c*d*L(y(x),z(x)) where c and d are constants or numbers.

It should also be able to expand things like L(c*y1(x)+d*y2(x),e*z1(x)+f*z2(x)).

Thanks.

So I am trying to solve a given ODE using calculated christoffel symbols found by maple, and in order to get the correct christoffel symbols, I need my function to be r=x-x_s, where x is not a function of t. However, I then have to solve the ODE where x is a function of t. Maple used the r value to find the christoffel symbols which has x in it, and now I want to find the origonal function of x(t), but I can't have x and x(t) in the same ODE. If I change r=x-x_s to r=x(t)-x_s, I get the wrong christoffel symbols. How can I solve my ODE?

I have a markov matrix that is 500x500. I need to take the standard deviation of the top row of this matrix after I raise it to high powers, like 10^17 by 10^12, (from a do loop.) I would also like ot make a histogram of this data too. 

 

Any ideas what I can do? 

I have a pair of markov matrices that are 250x250 and 500x500 in size. I am raising these matrices to high powers, like 10^17 by 10^12. (I'm using a do loop.) If I set digits:=15, Maple will use 100% of the processor that is available. If I set digits:=16+ Maple will only use 1 thread of my processor. Why? It is the same matrix same program. The only thing that changes is the digits of accuracy. This seems exactly backwards from what it should be. As a result, my AMD9590 processor will run full blast when I choose 15 digits of accuracy and gets the biggest matrix done in 1-2 hours. If i set the accuracy to 17 digits, it takes half a day or more to do the same thing!!! 2 digits of greater accuracy should not take an additional 20 hours!

 

Thanks 

Hi

I need a command or code to display numerical amount of parameter (i) in below textbox

e.g. display Element 2 instead of Element i when i is equal to 2

Hello,

How can i from a randomly generated 100 numbers, output the number of unique elements...

 

thank you very much.

 

 

hello, 

i need to use only looping to determine the larget integer in my random list...

here is how i put it together, but my result is incorrrect... Please help.

thank you

R:=rand(1..50)

seq(R(1..50),i=1..20)

L:=[%]

max:=proc(L,maxv : : evaln)

locali;

maxv:=L[i];

for i from 1 to nops(L) do

if eval(maxv)<L[i] then maxv:=L[i]end if;
end do;

end proc;

 

Hi all,

I want to design a procedure which can generate multiple loop automatically. While I  assign a value to it, it will create a multiple loop with same number of layers.    

For example,

P(1):

for i from 1 to n do
...
end do:

 

p(2):

for i from 1 to n do

for j from 1 to n do
...

end do: end do:

 

p(3)...

p(4)...

...

 

 

 

I'd appreciate any help on this topic. Thank a lot.

 

hello,

i am quite new into programming and i need help with writing a code that determines the largest integer in the list...

Please help..

Thank you 

I try to solve a set of differential equations with boundary conditions by dsolve command but I got this error:

--------------------------------------------------------------------------------------------------------------------------

odes := D2*(diff(P(x), x))/((3*D1*a+4*D2)*P(x))-(diff(S(x), x))/(q*S(x)-1) = 0, diff(S(x), `$`(x, 2))+(diff(S(x), x))*cotx+4*pi*(3*D1*a+4*D1)*P(x)/((q*S(x)-1)*D2) = 0

ics := P((1/2)*pi) = 1, S((1/2)*pi) = -1, (D(S))((1/2)*pi) = 0, (D(P))((1/2)*pi) = 0

sol := dsolve({ics, odes}, numeric);
Error, (in dsolve/numeric/process_input) input system must be an ODE system, got independent variables {x, (1/2)*pi}

--------------------------------------------------------------------------------------------------------------------------

Does any body knows what the problem is??

 

 

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