## Version 1.0.0

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### MA46 Sparse unsymmetric ﬁnite-element system: multifrontal

To solve one or more set of sparse unsymmetric linear equations $AX=B$ from ﬁnite-element applications, using a multifrontal elimination scheme. The matrix $A$ must be input by elements and be of the form

$A=\sum _{k=1}^{m}{A}^{\left(k\right)}$

where ${A}^{\left(k\right)}$ is nonzero only in those rows and columns that correspond to variables of the nodes of the $k$-th element. Optionally, the user may pass an additional matrix ${A}_{d}$ of coeﬃcients for the diagonal. $A$ is then of the form

$A=\sum _{k=1}^{m}{A}^{\left(k\right)}+{A}_{d}$

The right-hand side $B$ should be assembled through the summation

$B=\sum _{k=1}^{m}{B}^{\left(k\right)},$

before calling the solution routine.