solveq¶

Purpose:

Solve equation system.

Syntax:

a = solveq(K, f)
a = solveq(K, f, bcP, bc)
[a, r] = solveq(K, f, bc)

Description:

The function solveq solves the equation system

\[\mathbf{K}\;\mathbf{a} = \mathbf{f}\]

where \(\mathbf{K}\) is a matrix and \(\mathbf{a}\) and \(\mathbf{f}\) are vectors.

The matrix \(\mathbf{K}\) and the vector \(\mathbf{f}\) must be predefined. The solution of the system of equations is stored in a vector \(\mathbf{a}\) which is created by the function.

If some values of \(\mathbf{a}\) are to be prescribed, the row number and the corresponding values are given in the boundary condition matrix

bc\(= \left[ \begin{array}{c} dof_1 \\ dof_2 \\ \vdots \\ dof_{nbc} \end{array} \quad \begin{array}{c} u_1 \\ u_2 \\ \vdots \\ u_{nbc} \end{array} \right]\)

where the first column contains the row numbers and the second column the corresponding prescribed values.

If r is given in the function, support forces are computed according to

mathbf{r}\(= \mathbf{K}\;\mathbf{a} - \mathbf{f}\)