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Extract coefficients of partial differential equation

extracts the coefficients of a partial differential equation (PDE) as a structure of
double-precision numbers and function handles, which can be used as input of the
`coeffs`

= pdeCoefficients(`pdeeq`

,`u`

)`specifyCoefficients`

function in Partial Differential Equation Toolbox™.

`pdeeq`

is a scalar PDE or a PDE system in symbolic form that is a
function of `u`

. The `pdeCoefficients`

function converts
`pdeeq`

into a system of equations of the form

$$m\frac{{\partial}^{2}u}{\partial {t}^{2}}+d\frac{\partial u}{\partial t}-\nabla \xb7\left(c\otimes \nabla u\right)+au=f$$

and returns the structure `coeffs`

that contains the
coefficients `m`

, `d`

, `c`

,
`a`

, and `f`

. For more information, see Equations You Can Solve Using PDE Toolbox (Partial Differential Equation Toolbox).

If `pdeCoefficients`

cannot convert a PDE into the divergence form
above, then it issues a warning message and writes all remaining gradients to the
`f`

coefficient. PDE Toolbox will be unable to solve this type of
PDE.

`diff`

| `laplacian`

| `pdeCoefficientsToDouble`

| `syms`

| `specifyCoefficients`

(Partial Differential Equation Toolbox)