Advanced Search

delvin

50 Reputation

5 Badges

2 years, 148 days
Contact delvin

MaplePrimes Activity


These are replies submitted by delvin

@Thomas Richard   Yes, I am n...

delvin 50
March 15 2023
0 0

@Thomas Richard 

 Yes, I am not very familiar with the site and I am a beginner in Maple software. I need this equation with its answers and graph for my project. Now I use the dsole command to solve it to see if it gets the same answer?
Is it possible that it cannot be solved with this command because it is nonlinear?
My system hangs when running this command code and unfortunately it doesn't stop, I have to turn off the system.
Thank you very much for taking the time to answer my question.
Thank you for your guidance.

 

@Thomas Richard    Thank you ...

delvin 50
March 10 2023
0 0

@Thomas Richard 

  Thank you dear Richard,

@Thomas Richard  thanks ...

delvin 50
March 09 2023
0 0

@Thomas Richard 

 Unfortunately, it did not answer.

 

@mmcdara  thanks...

delvin 50
February 14 2023
0 0

@mmcdara

 thanks

@sursumCorda   ...

delvin 50
February 13 2023
0 0

@sursumCorda 

 

I don't know why it makes an error?...

delvin 50
October 18 2022
0 0

@tomleslie 
 

``

``

> 

restart
> 

with(student)

U := a[0]+sum(-a[i]*tanh(xi)^i, i = 1 .. 1)+sum(-b[i]*tanh(xi)^(-i), i = 1 .. 1)

a[0]-a[1]*tanh(xi)-b[1]/tanh(xi)

 (1)
> 

``
> 

``
> 

``

eq := 6*c^2*U(xi)+9*U(xi)^2*c+3*U(xi)^3-2*(diff(U, `$`(xi, 2)))

6*c^2*(a[0](xi)-a[1](xi)*(tanh(xi))(xi)-b[1](xi)/(tanh(xi))(xi))+9*(a[0](xi)-a[1](xi)*(tanh(xi))(xi)-b[1](xi)/(tanh(xi))(xi))^2*c+3*(a[0](xi)-a[1](xi)*(tanh(xi))(xi)-b[1](xi)/(tanh(xi))(xi))^3-4*a[1]*tanh(xi)*(1-tanh(xi)^2)+4*b[1]*(1-tanh(xi)^2)^2/tanh(xi)^3+4*b[1]*(1-tanh(xi)^2)/tanh(xi)

 (2)
> 

``

simplify(eq); fin1 := simplify(numer(%))

-3*a[1](xi)^3*(tanh(xi))(xi)^6*tanh(xi)^3+9*tanh(xi)^3*a[1](xi)^2*(c+a[0](xi))*(tanh(xi))(xi)^5-6*(c^2+3*c*a[0](xi)+(3/2)*a[0](xi)^2+(3/2)*a[1](xi)*b[1](xi))*tanh(xi)^3*a[1](xi)*(tanh(xi))(xi)^4+(18*tanh(xi)^3*b[1](xi)*(c+a[0](xi))*a[1](xi)+3*tanh(xi)^3*a[0](xi)^3+9*c*tanh(xi)^3*a[0](xi)^2+6*c^2*tanh(xi)^3*a[0](xi)+4*(tanh(xi)-1)*(tanh(xi)+1)*(a[1]*tanh(xi)^4-b[1]))*(tanh(xi))(xi)^3-6*(c^2+3*c*a[0](xi)+(3/2)*a[0](xi)^2+(3/2)*a[1](xi)*b[1](xi))*tanh(xi)^3*b[1](xi)*(tanh(xi))(xi)^2+9*tanh(xi)^3*b[1](xi)^2*(c+a[0](xi))*(tanh(xi))(xi)-3*b[1](xi)^3*tanh(xi)^3

 (3)

subs(tanh(xi) = Psi, fin1); fin := simplify(%)

-3*a[1](xi)^3*Psi(xi)^6*Psi^3+9*Psi^3*a[1](xi)^2*(c+a[0](xi))*Psi(xi)^5-6*(c^2+3*c*a[0](xi)+(3/2)*a[0](xi)^2+(3/2)*a[1](xi)*b[1](xi))*Psi^3*a[1](xi)*Psi(xi)^4+(18*Psi^3*b[1](xi)*(c+a[0](xi))*a[1](xi)+3*Psi^3*a[0](xi)^3+9*c*Psi^3*a[0](xi)^2+6*c^2*Psi^3*a[0](xi)+4*(Psi-1)*(Psi+1)*(Psi^4*a[1]-b[1]))*Psi(xi)^3-6*(c^2+3*c*a[0](xi)+(3/2)*a[0](xi)^2+(3/2)*a[1](xi)*b[1](xi))*Psi^3*b[1](xi)*Psi(xi)^2+9*Psi^3*b[1](xi)^2*(c+a[0](xi))*Psi(xi)-3*b[1](xi)^3*Psi^3

 (4)

for i from 0 to degree(fin, Psi) do EQ[i] := simplify(coeff(fin, Psi, i)) end do

Error, final value in for loop must be numeric or character

  

``

``

``


 

Download ger01.mw

@tomleslie       T...

delvin 50
October 17 2022
0 0

@tomleslie 

  

  Thank you for taking time out of your busy day.
   Sincerely,

   delvin

@rcorless    ok...

delvin 50
October 16 2022
0 0

@rcorless 

   The equation is correct, but I didn't pay attention, I wrote some in my own language,sorry.

@Rouben Rostamian      S...

delvin 50
October 16 2022
0 0

@Rouben Rostamian  

   Sorry, I was not paying attention.

      Thanks ocean.

@tomleslie   Ok, I want to ch...

delvin 50
October 10 2022
0 0

@tomleslie 

 Ok, I want to check the different solutions of the equation.

 

  Thanks a million, You made my day.

 

@tomleslie    Thank osean...

delvin 50
October 09 2022
0 0

@tomleslie 

   Thank osean very much for your time.

 "Because the answers are not what I want , The answers obtained are obvious."

m4.mw

@Joe Riel  This is the code I ...

delvin 50
October 09 2022
0 0

@Joe Riel 

This is the code I wrote, but it didn't get a good answer

> 

restart
> 

with(student)

U := a[0]+sum(-a[i]*tanh(xi[n])^i, i = 1 .. 1)+sum(-b[i]*tanh(xi[n])^(-i), i = 1 .. 1)

a[0]-a[1]*tanh(xi[n])-b[1]/tanh(xi[n])

 (1)
> 

u(xi[n+1]) := a[0]-a[1]*(tanh(xi[n])+tanh(d))/(1+tanh(xi[n])*tanh(d))-b[1]*(1+tanh(xi[n])*tanh(d))/(tanh(xi[n])+tanh(d))

a[0]-a[1]*(tanh(xi[n])+tanh(d))/(1+tanh(xi[n])*tanh(d))-b[1]*(1+tanh(xi[n])*tanh(d))/(tanh(xi[n])+tanh(d))

 (2)
> 

u(xi[n-1]) := a[0]-a[1]*(tanh(xi[n])-tanh(d))/(1+tanh(xi[n])*tanh(d))-b[1]*(1+tanh(xi[n])*tanh(d))/(tanh(xi[n])-tanh(d))

a[0]-a[1]*(tanh(xi[n])-tanh(d))/(1+tanh(xi[n])*tanh(d))-b[1]*(1+tanh(xi[n])*tanh(d))/(tanh(xi[n])-tanh(d))

 (3)

eq := c*(diff(U, xi))-(U^2+U*beta+alpha)*(u(xi[n+1])-u(xi[n-1]))

-((a[0]-a[1]*tanh(xi[n])-b[1]/tanh(xi[n]))^2+(a[0]-a[1]*tanh(xi[n])-b[1]/tanh(xi[n]))*beta+alpha)*(-a[1]*(tanh(xi[n])+tanh(d))/(1+tanh(xi[n])*tanh(d))-b[1]*(1+tanh(xi[n])*tanh(d))/(tanh(xi[n])+tanh(d))+a[1]*(tanh(xi[n])-tanh(d))/(1+tanh(xi[n])*tanh(d))+b[1]*(1+tanh(xi[n])*tanh(d))/(tanh(xi[n])-tanh(d)))

 (4)
> 

U := a[0]-a[1]*tanh(xi[n])-b[1]/tanh(xi[n])

a[0]-a[1]*tanh(xi[n])-b[1]/tanh(xi[n])

 (5)

simplify(eq); fin1 := simplify(numer(%))

-2*(tanh(xi[n])^4*a[1]^2-a[1]*(beta+2*a[0])*tanh(xi[n])^3+(beta*a[0]+a[0]^2+2*a[1]*b[1]+alpha)*tanh(xi[n])^2-b[1]*(beta+2*a[0])*tanh(xi[n])+b[1]^2)*tanh(d)*((b[1]*tanh(d)^2-a[1])*tanh(xi[n])^2+2*tanh(xi[n])*tanh(d)*b[1]+tanh(d)^2*a[1]+b[1])

 (6)

subs(tanh(xi[n]) = Psi, fin1); fin := simplify(%)

2*(Psi^4*a[1]^2-a[1]*(beta+2*a[0])*Psi^3+(beta*a[0]+a[0]^2+2*a[1]*b[1]+alpha)*Psi^2-b[1]*(beta+2*a[0])*Psi+b[1]^2)*((-Psi^2*b[1]-a[1])*tanh(d)^2-2*Psi*tanh(d)*b[1]+Psi^2*a[1]-b[1])*tanh(d)

 (7)

for i from 0 to degree(fin, Psi) do EQ[i] := simplify(coeff(fin, Psi, i)) end do

2*a[1]^2*(-b[1]*tanh(d)^2+a[1])*tanh(d)

 (8)

Eqs := {seq(EQ[i], i = 0 .. 6)}

Sol := solve(Eqs, {c, a[1], b[1]})

{c = c, a[1] = 0, b[1] = 0}

 (9)

 

Download m3.mw

@acer  okey...

delvin 50
September 12 2022
0 0

@acer 

okey

@dharr  thanks an ocean...

delvin 50
July 30 2022
0 0

@dharr thanks an ocean

How can I compare the values of A_0, A_1...

delvin 50
July 30 2022
0 0

@dharr Thanks

NULL

> 

restart;
with(PDEtools):
> 


pde2:=-lambda*diff(y(xi),xi)+y(xi)*diff(y(xi),xi)+diff(y(xi),xi$2)=0;

-lambda*(diff(y(xi), xi))+y(xi)*(diff(y(xi), xi))+diff(diff(y(xi), xi), xi) = 0

 (1)
> 

 

NULL

> 

phi(xi):=(p[1]*exp(q[1]*xi)+p[2]*exp(q[2]*xi))/(p[3]*exp(q[3]*xi)+p[4]*exp(q[4]*xi));
eval(phi(xi),[p[1]=I,p[2]=-I,p[3]=1,p[4]=1,q[1]=I,q[2]=-I,q[3]=I,q[4]=-I]);
simplify(%);
phi(xi):=%;
U(xi):=A[0]+sum(A[d]*phi(xi)^d,d=1)+sum(B[d]*phi(xi)^(-d),d=1);

(p[1]*exp(q[1]*xi)+p[2]*exp(q[2]*xi))/(p[3]*exp(q[3]*xi)+p[4]*exp(q[4]*xi))

  

(I*exp(I*xi)-I*exp(-I*xi))/(exp(I*xi)+exp(-I*xi))

  

-sin(xi)/cos(xi)

  

-sin(xi)/cos(xi)

  

A[0]-A[1]*sin(xi)/cos(xi)-B[1]*cos(xi)/sin(xi)

 (2)
> 

subs(y(xi)=U(xi),pde2);

-lambda*(diff(A[0]-A[1]*sin(xi)/cos(xi)-B[1]*cos(xi)/sin(xi), xi))+(A[0]-A[1]*sin(xi)/cos(xi)-B[1]*cos(xi)/sin(xi))*(diff(A[0]-A[1]*sin(xi)/cos(xi)-B[1]*cos(xi)/sin(xi), xi))+diff(diff(A[0]-A[1]*sin(xi)/cos(xi)-B[1]*cos(xi)/sin(xi), xi), xi) = 0

 (3)
 

 

Download test1.mw

5 6 7 8 Page 7 of 8