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Dr. farahnaz farahnaz

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error for dsolve differential equation.....

farahnaz 15 Maple 2016
ode differential-equation dsolve
October 12 2016
1 4

hi..i have a problem for solving this nonlinear differential equationerror.mw

restart; Digite := 200; L := 100*10^(-9)

1/10000000

 (1)

EQ11 := -3.000000000*10^(-8)+3.815358072*sin(3.141592654*10^7*x)+9.534375000*10^(-30)*(diff(w(x), x, x, x, x))-2.383593750*10^(-60)*(diff(w(x), x, x, x, x, x, x))-5.085000000*10^(-13)*(diff(w(x), x))*(diff(u(x), x, x))-7.627500000*10^(-13)*(diff(w(x), x))^2*(diff(w(x), x, x))-5.085000000*10^(-13)*(diff(w(x), x, x))*(diff(u(x), x))+0.2410290000e-5*(diff(w(x), x, x)):

EQ2 := 5.650000000*10^(-20)*(diff(u(x), x, x, x, x))-226000000000*(diff(u(x), x, x))-226000000000*(diff(w(x), x))*(diff(w(x), x, x)):

dsys3 := {EQ11, EQ2, u(0) = 0, u(L) = 0, w(0) = 0, w(L) = 0, (D(u))(0) = 0, (D(u))(L) = 0, ((D@@2)(w))(0) = 0, ((D@@2)(w))(L) = 0, ((D@@4)(w))(0) = 0, ((D@@4)(w))(L) = 0}; res := dsolve(dsys3, numeric, initmesh = 1024, abserr = 0.1e-4); res(0.1e-9)

res(0.1e-9)

 (2)

############################################################CHANGE OF VARIABLE:::           x=y*L

bcs := {u(0) = 0, u(L) = 0, w(0) = 0, w(L) = 0, (D(u))(0) = 0, (D(u))(L) = 0, ((D@@2)(w))(0) = 0, ((D@@2)(w))(L) = 0, ((D@@4)(w))(0) = 0, ((D@@4)(w))(L) = 0}; sys := {EQ11, EQ2}; sys2 := PDEtools:-dchange({x = L*y, u(x) = g2(y), w(x) = g1(y)}, sys, [g1, g2, y]); solve(sys2, {diff(g2(y), y, y, y, y), diff(g1(y), y, y, y, y, y, y)}); bcs3 := {g1(0) = 0, g1(1) = 0, g2(0) = 0, g2(1) = 0, (D(g2))(0) = 0, (D(g2))(1) = 0, ((D@@2)(g1))(0) = 0, ((D@@2)(g1))(1) = 0, ((D@@4)(g1))(0) = 0, ((D@@4)(g1))(1) = 0}; res3 := dsolve(`union`(sys2, bcs3), numeric, maxmesh = 2024, abserr = 0.1e-4); plots:-odeplot(res3, [seq([y, (cat(g, i))(y)], i = 1 .. 2)], 0 .. 1)

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

  

``

 

Download error.mw

please help me

thanks...

 

how i can pdsolve this equation?...

farahnaz 15 Maple 2016
pdsolve
September 26 2016
1 5

hi

please help to me for solve this equation via pdsolve?

thanks

dsove2.mw

> 

restart
> 

f := 1; k := 1; h := 1
> 

PDE := diff((diff(rho*H(rho, z), rho))/rho, rho)+diff(H(rho, z), z, z)+k^2*H(rho, z) = f

-(H(rho, z)+rho*(diff(H(rho, z), rho)))/rho^2+(2*(diff(H(rho, z), rho))+rho*(diff(diff(H(rho, z), rho), rho)))/rho+diff(diff(H(rho, z), z), z)+H(rho, z) = 1

 (1)
> 

NULL
> 

NULL
> 

NULL
> 

NULL
> 

sol3 := dsolve([PDE, (D[2](H))(rho, -h) = 0, (D[2](H))(rho, 0) = 0], H(rho, z))
> 

NULL



Download dsove2.mw

 

 

 

how i can plot four curve in one figure ...

farahnaz 15 Maple 2016
plot excel
September 14 2016
1 2

hi

how i can plot 4 curve in one graph in maple??

this data is given in excel format as below

thanks

16.3.xlsx

Error, (in pdsolve/numeric/process_PDEs)...

farahnaz 15 Maple 2016
pde pdsolve differential-equations
August 24 2016
1 8

hi .may every one help me for pdsolve this differential equations?

all initial boundary condition are zero

thanks...

pdeSol_(1).mw

 

> 

#
# Define some parameters
#
  sigma := 10; N := 0; beta := 1; alpha := 1; PDE1 := diff(w(X, theta, t), X, X, X, X)+2*alpha^2*(diff(w(X, theta, t), theta, theta, X, X))+alpha^4*(diff(w(X, theta, t), theta, theta, theta, theta))-N*(diff(w(X, theta, t), X, X))+diff(w(X, theta, t), t, t)-beta*w(X, theta, t)-sigma = 0

10

  

0

  

1

  

1

  

diff(diff(diff(diff(w(X, theta, t), X), X), X), X)+2*(diff(diff(diff(diff(w(X, theta, t), X), X), theta), theta))+diff(diff(diff(diff(w(X, theta, t), theta), theta), theta), theta)-10+diff(diff(w(X, theta, t), t), t)-w(X, theta, t) = 0

 (1)
> 

#
# Define the PDES
#
  PDEs:= { diff(w(X, theta, t), X, X, X, X)+2*alpha^2*(diff(w(X, theta, t), theta, theta, X, X))+alpha^4*(diff(w(X, theta, t), theta, theta, theta, theta))-N*(diff(w(X, theta, t), X, X))+diff(w(X, theta, t), t, t)-beta*w(X, theta, t)-sigma = 0
   };

{diff(diff(diff(diff(w(X, theta, t), X), X), X), X)+2*(diff(diff(diff(diff(w(X, theta, t), X), X), theta), theta))+diff(diff(diff(diff(w(X, theta, t), theta), theta), theta), theta)-10+diff(diff(w(X, theta, t), t), t)-w(X, theta, t) = 0}

 (2)
> 

#
# Set of boundary conditions at x=1.
#
   bcs1:= { D[1](w)(1,theta, t) = 0,
              w(1,theta, t) = 0
         };

{w(1, theta, t) = 0, (D[1](w))(1, theta, t) = 0}

 (3)
> 

#
# Set of boundary conditions at x=0
#
  bcs2:= {    w(0,theta, t)=0,
           D[1](w)(0,theta, t)=0
         };

{w(0, theta, t) = 0, (D[1](w))(0, theta, t) = 0}

 (4)
> 

#
# Set of boundary conditions at t=0
#
  bcs3:= { w(x,theta,0)=0,
          
           D[2](w)(x,theta,0)=0 };
           

{w(x, theta, 0) = 0, (D[2](w))(x, theta, 0) = 0}

 (5)
> 

 

> 


  pdsolve( PDEs, `union`(bcs1, bcs2, bcs3), numeric);

Error, (in pdsolve/numeric/process_PDEs) can only numerically solve PDE with two independent variables, got {X, t, theta}

  
> 

 

 

Download pdeSol_(1).mw

error for dsolve equations ''Length of o...

farahnaz 15 Maple 18
dsolve
August 01 2016
1 4

hi

please help me for dsolve this equation...

error_length.mw

dsys3 := {(63/20000000)*(diff(u(x), x, x, x, x))-120000000000*(diff(u(x), x, x))-60000000000*(diff(w(x), x, x)), -2.100000000*10^(-30)*(diff(w(x), x, x, x, x, x, x))-4.860000000*10^(-14)*(diff(w(x), x, x, x, x))-(2400*(diff(u(x), x, x)+(diff(w(x), x))*(diff(w(x), x, x))))*(diff(w(x), x))-(1/50000000)*(diff(w(x), x, x))*(120000000000*(diff(u(x), x))+60000000000*(diff(w(x), x))^2-120000000000), u(0) = 0, u(1/2000000) = 0, w(0) = 0, w(1/2000000) = 0, (D(u))(0) = 0, (D(u))(1/2000000) = 0, ((D@@2)(w))(0) = 0, ((D@@2)(w))(1/2000000) = 0, ((D@@4)(w))(0) = 0, ((D@@4)(w))(1/2000000) = 0}

{(63/20000000)*(diff(diff(diff(diff(u(x), x), x), x), x))-120000000000*(diff(diff(u(x), x), x))-60000000000*(diff(diff(w(x), x), x)), -0.2100000000e-29*(diff(diff(diff(diff(diff(diff(w(x), x), x), x), x), x), x))-0.4860000000e-13*(diff(diff(diff(diff(w(x), x), x), x), x))-2400*(diff(diff(u(x), x), x)+(diff(w(x), x))*(diff(diff(w(x), x), x)))*(diff(w(x), x))-(1/50000000)*(diff(diff(w(x), x), x))*(120000000000*(diff(u(x), x))+60000000000*(diff(w(x), x))^2-120000000000), u(0) = 0, u(1/2000000) = 0, w(0) = 0, w(1/2000000) = 0, (D(u))(0) = 0, (D(u))(1/2000000) = 0, ((D@@2)(w))(0) = 0, ((D@@2)(w))(1/2000000) = 0, ((D@@4)(w))(0) = 0, ((D@@4)(w))(1/2000000) = 0}

 (1)

dsolve(dsys3, numeric, initmesh = 3024, abserr = 0.1e-4)

`[Length of output exceeds limit of 1000000]`

 (2)

``


Download error_length.mw

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