CoefficientAssignment Properties

Coefficient assignments

A CoefficientAssignment object contains a description of the PDE coefficients. A PDEModel container has a vector of CoefficientAssignment objects in its EquationCoefficients.CoefficientAssignments property.

Coefficients are the m, d, c, a, and f variables in the PDE

$$m\frac{{\partial }^{2}u}{\partial t^2}+d\frac{\partial u}{\partial t}-\nabla ·\left(c\nabla u\right)+au=f$$

or the eigenvalue problem

$$\begin{array}{l}-\nabla ·\left(c\nabla u\right)+au=\lambda du\\ \text{or}\\ -\nabla ·\left(c\nabla u\right)+au={\lambda }^{2}mu\end{array}$$

Create coefficients for your model using the specifyCoefficients function.

Properties

RegionType — Region type

'face' | 'cell'

Region type, specified as 'face' for a 2-D region, or 'cell' for a 3-D region.

Data Types: char | string

RegionID — Region ID

vector of positive integers

Region ID, specified as a vector of positive integers. To determine which ID corresponds to which portion of the geometry, use the pdegplot function. Set the 'FaceLabels' name-value pair to 'on'.

Data Types: double

m — Second-order time derivative coefficient

scalar | column vector | function handle

Second-order time derivative coefficient, specified as a scalar, column vector, or function handle. For details of the m coefficient specification, see m, d, or a Coefficient for specifyCoefficients.

Data Types: double | function_handle
Complex Number Support: Yes

d — First-order time derivative coefficient

scalar | column vector | function handle

First-order time derivative coefficient, specified as a scalar, column vector, or function handle. For details of the d coefficient specification, see m, d, or a Coefficient for specifyCoefficients.

Data Types: double | function_handle
Complex Number Support: Yes

c — Second-order space derivative coefficient

scalar | column vector | function handle

Second-order space derivative coefficient, specified as a scalar, column vector, or function handle. For details of the c coefficient specification, see c Coefficient for specifyCoefficients.

Data Types: double | function_handle
Complex Number Support: Yes

a — Solution multiplier coefficient

scalar | column vector | function handle

Solution multiplier coefficient, specified as a scalar, column vector, or function handle. For details of the a coefficient specification, see m, d, or a Coefficient for specifyCoefficients.

Data Types: double | function_handle
Complex Number Support: Yes

f — Source coefficient

scalar | column vector | function handle

Source coefficient, specified as a scalar, column vector, or function handle. For details of the f coefficient specification, see f Coefficient for specifyCoefficients.

Data Types: double | function_handle
Complex Number Support: Yes

Version History

Introduced in R2016a