This is machine translation

Translated by Microsoft
Mouse over text to see original. Click the button below to return to the English verison of the page.

Systems in the PDE App

You can enter coefficients for a system with N = 2 equations in the PDE app. To do so, open the PDE app and select Generic System.

Then select PDE > PDE Specification.

Enter character expressions for coefficients using the form in Coefficients for Scalar PDEs in PDE App, with additional options for nonlinear equations. The additional options are:

  • Represent the ith component of the solution u using 'u(i)' for i = 1 or 2.

  • Similarly, represent the ith components of the gradients of the solution u using 'ux(i)' and 'uy(i)' for i = 1 or 2.

    Note:   For elliptic problems, when you include coefficients u(i), ux(i), or uy(i), you must use the nonlinear solver. Select Solve > Parameters > Use nonlinear solver.

Do not use quotes or unnecessary spaces in your entries.

For higher-dimensional systems, do not use the PDE app. Represent your problem coefficients at the command line.

You can enter scalars into the c matrix, corresponding to these equations:


If you need matrix versions of any of the cij coefficients, enter expressions separated by spaces. You can give 1-, 2-, 3-, or 4-element matrix expressions. These mean:

  • 1-element expression: (c00c)

  • 2-element expression: (c(1)00c(2))

  • 3-element expression: (c(1)c(2)c(2)c(3))

  • 4-element expression: (c(1)c(3)c(2)c(4))

For example, these expressions show one of each type (1-, 2-, 3-, and 4-element expressions)

These expressions correspond to the equations


Was this topic helpful?