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Deflection of a Square Plate Calculated With PDE Toolbox

Deflection of a Square Plate Calculated With PDE Toolbox

4 years ago | 3 downloads |

Answered

Solving 2 PDEs across one domain.

This documentation page shows how to specify an f-coefficient on a specific domain: <http://www.mathworks.com/help/pde/ug/sca...

Solving 2 PDEs across one domain.

This documentation page shows how to specify an f-coefficient on a specific domain: <http://www.mathworks.com/help/pde/ug/sca...

7 years ago | 0

| accepted

Solved

Times 2 - START HERE

Try out this test problem first. Given the variable x as your input, multiply it by two and put the result in y. Examples:...

7 years ago

Solved

Make the vector [1 2 3 4 5 6 7 8 9 10]

In MATLAB, you create a vector by enclosing the elements in square brackets like so: x = [1 2 3 4] Commas are optional, s...

7 years ago

Answered

Simulation of coupled partial differential equation using MATLAB.

I took a look at your attachment and think I understand most, but not all, of the problem you are trying to solve (I don't under...

Simulation of coupled partial differential equation using MATLAB.

I took a look at your attachment and think I understand most, but not all, of the problem you are trying to solve (I don't under...

7 years ago | 0

| accepted

Answered

Problems with LDL factorization

Have you tried solving the over-determined system directly: x = A\b; Computing using the normal equations, A'*A, is almost...

Problems with LDL factorization

Have you tried solving the over-determined system directly: x = A\b; Computing using the normal equations, A'*A, is almost...

7 years ago | 0

Answered

Can I use Poisson equation or any equation with desired parameters in PDE Toolbox using Rectangular shape?

Take a look at this example: <http://www.mathworks.com/help/pde/ug/electrostatics.html> Bill

Can I use Poisson equation or any equation with desired parameters in PDE Toolbox using Rectangular shape?

Take a look at this example: <http://www.mathworks.com/help/pde/ug/electrostatics.html> Bill

7 years ago | 0

Answered

Why aren't the essential boundary conditions fulfilled?

I ran this example in R2014a of MATLAB and I do get -1 at the lower left corner (and upper right) I created the example in pd...

Why aren't the essential boundary conditions fulfilled?

I ran this example in R2014a of MATLAB and I do get -1 at the lower left corner (and upper right) I created the example in pd...

7 years ago | 0

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Answered

Solve parabolic coupled PDE's using MATLAB's pdepe solver?

Yes, pdepe can definitely solve systems of pde. In general, the u argument to the functions you define has as many rows as ther...

Solve parabolic coupled PDE's using MATLAB's pdepe solver?

Yes, pdepe can definitely solve systems of pde. In general, the u argument to the functions you define has as many rows as ther...

7 years ago | 0

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Answered

structured quadrilateral mesh in PDE Toolbox

There is no support for quadrilateral elements in PDE Toolbox-- either in the meshers or the computational modules. However, if...

structured quadrilateral mesh in PDE Toolbox

There is no support for quadrilateral elements in PDE Toolbox-- either in the meshers or the computational modules. However, if...

7 years ago | 0

| accepted

Answered

How to define a temperature dependent parameters in a PDE Toolbox?

Yes, PDE Toolbox allows the coefficients to be functions of the dependent variables (e.g. temperature). This documentation page ...

How to define a temperature dependent parameters in a PDE Toolbox?

Yes, PDE Toolbox allows the coefficients to be functions of the dependent variables (e.g. temperature). This documentation page ...

7 years ago | 2

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Answered

Setting up the initial conditions for BVP4C?

From your call to bvpinit where you have this [0.01; 0.9] for the initial guess, it looks like you have 2 differential equation...

Setting up the initial conditions for BVP4C?

From your call to bvpinit where you have this [0.01; 0.9] for the initial guess, it looks like you have 2 differential equation...

7 years ago | 1

Answered

Matlab hyperbolic PDE equation errors

There are several ways to define PDE Toolbox coefficients that vary spatially. But, defining the value of the coefficient at eve...

Matlab hyperbolic PDE equation errors

There are several ways to define PDE Toolbox coefficients that vary spatially. But, defining the value of the coefficient at eve...

7 years ago | 1

Answered

How to solve system of three nonlinear PDE?

pdenonlin is for solving only PDE that are not a function of time. However, the parabolic function can solve equations that a...

How to solve system of three nonlinear PDE?

pdenonlin is for solving only PDE that are not a function of time. However, the parabolic function can solve equations that a...

7 years ago | 0

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Answered

Solve a non linear differential equation systems with only boundary conditions

You have a system of two first order differential equations so you need just two boundary conditions. I would guess that specify...

Solve a non linear differential equation systems with only boundary conditions

You have a system of two first order differential equations so you need just two boundary conditions. I would guess that specify...

7 years ago | 0

Answered

Reg. PDEPE 's internal discretization of time

pdepe uses the variable time step ODE solver, ode15s, internally. http://www.mathworks.com/help/matlab/ref/ode15s.html The...

Reg. PDEPE 's internal discretization of time

pdepe uses the variable time step ODE solver, ode15s, internally. http://www.mathworks.com/help/matlab/ref/ode15s.html The...

7 years ago | 1

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Answered

Insert f coefficient in pdetool

Do you calculate F in fcoeff? If so, you can make it a global variable and it will retain its value between calls to fcoeff. ...

Insert f coefficient in pdetool

Do you calculate F in fcoeff? If so, you can make it a global variable and it will retain its value between calls to fcoeff. ...

7 years ago | 0

Answered

pdepe daeic12 (line 77) eror

I don't see any boundary conditions on c3. I think this may be the cause of your problem. Bill

pdepe daeic12 (line 77) eror

I don't see any boundary conditions on c3. I think this may be the cause of your problem. Bill

7 years ago | 0

Answered

Error solving simultaneous PDEs.

The first thing I should say is that pdepe is designed to solve systems of parabolic and elliptic PDEs. Practically this means t...

Error solving simultaneous PDEs.

The first thing I should say is that pdepe is designed to solve systems of parabolic and elliptic PDEs. Practically this means t...

7 years ago | 0

Answered

create sparse matrix from diagonal arrays

This doesn't exactly answer your question but still may be useful. This example: http://math.mit.edu/cse/codes/mit18086_poiss...

create sparse matrix from diagonal arrays

This doesn't exactly answer your question but still may be useful. This example: http://math.mit.edu/cse/codes/mit18086_poiss...

7 years ago | 0

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Answered

How to implement irregular, time-dependent boundary condition in PDEPE function?

I think that pr = interp1(timedata, tempdata, t) - ur; may be what you need. Assuming the lengths of timedata and temp...

How to implement irregular, time-dependent boundary condition in PDEPE function?

I think that pr = interp1(timedata, tempdata, t) - ur; may be what you need. Assuming the lengths of timedata and temp...

7 years ago | 1

| accepted

Answered

How can I solve a PDE with given coefficients in time?

Take a look at this example: <http://www.mathworks.com/help/pde/ug/nonlinear-heat-transfer-in-a-thin-plate.html Nonlinear Hea...

How can I solve a PDE with given coefficients in time?

Take a look at this example: <http://www.mathworks.com/help/pde/ug/nonlinear-heat-transfer-in-a-thin-plate.html Nonlinear Hea...

7 years ago | 0

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Answered

Function of boundary conditions PDEPE

To set the temperature at each end to fittedmodel(t), you would define: pl = ul-fittedmodel(t); pr = ur-fittedmodel(t); ...

Function of boundary conditions PDEPE

To set the temperature at each end to fittedmodel(t), you would define: pl = ul-fittedmodel(t); pr = ur-fittedmodel(t); ...

7 years ago | 0

Answered

calculate the capacitance with PDE toolbox

One of the simplest ways to calculate capacitance using PDE Toolbox is from the energy: C = 2*U/V^2 where U is the electrostatic...

calculate the capacitance with PDE toolbox

One of the simplest ways to calculate capacitance using PDE Toolbox is from the energy: C = 2*U/V^2 where U is the electrostatic...

7 years ago | 1

| accepted

Answered

How to control times at which PDE Toolbox solves a parabolic equation?

I'm afraid I wasn't able to run your example. I believe that your fcoeff function has an error in it. I did take a look at th...

How to control times at which PDE Toolbox solves a parabolic equation?

I'm afraid I wasn't able to run your example. I believe that your fcoeff function has an error in it. I did take a look at th...

7 years ago | 0

| accepted

Answered

Calculation of Jacobian for ode15s in hyperbolic/parabolic-Solver?

If the Jacobian is a function of the dependent variables (or time), ode15s will typically call pdehypdf many times during a com...

Calculation of Jacobian for ode15s in hyperbolic/parabolic-Solver?

If the Jacobian is a function of the dependent variables (or time), ode15s will typically call pdehypdf many times during a com...

7 years ago | 0

Answered

Calculation of Jacobian for ode15s in hyperbolic/parabolic-Solver?

Hi Lena, Yes, you are correct that the Jacobian calculated in parabolic/hyperbolic is only approximate. However, in my experi...

Calculation of Jacobian for ode15s in hyperbolic/parabolic-Solver?

Hi Lena, Yes, you are correct that the Jacobian calculated in parabolic/hyperbolic is only approximate. However, in my experi...

7 years ago | 0

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Answered

How to control times at which PDE Toolbox solves a parabolic equation?

>This does not yield correct results at the time values I ask it to plot the results So, why don't you request results at the...

How to control times at which PDE Toolbox solves a parabolic equation?

>This does not yield correct results at the time values I ask it to plot the results So, why don't you request results at the...

7 years ago | 0

Answered

eigs - Error with ARPACK routine znaupd: info = -8

I'm not certain what the problem is but I can suggest something to try. I'll assume you really want around 20 eigenvalues. By...

eigs - Error with ARPACK routine znaupd: info = -8

I'm not certain what the problem is but I can suggest something to try. I'll assume you really want around 20 eigenvalues. By...

7 years ago | 0

Answered

Does hyperbolic-solver really use a nonlinear solver?!

Hi, Unfortunately, I believe you have uncovered a bug in the hyperbolic function that occurs when you have a nonlinear equati...

Does hyperbolic-solver really use a nonlinear solver?!

Hi, Unfortunately, I believe you have uncovered a bug in the hyperbolic function that occurs when you have a nonlinear equati...

7 years ago | 0

| accepted