The LUMP Function

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The LUMP Function

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The LUMP function creates a field on the finite element mesh, and saves a single value of the argument expression in each cell of the finite element mesh.  The value stored for each cell is the average value of the argument expression over the cell, and is treated as a constant over the cell.

The LUMP function may be used to block ill-behaved functions from differentiation in the derivative computation for Newton's method, or to avoid expensive re-computation of complex functions.

The normal use for LUMP is in the DEFINITIONS section, as in

name = LUMP ( expression )

 

Note: This definition of LUMP(F) is NOT the same as the "lumped parameters" frequently referred to in finite element literature.

 

Example:

Samples | Usage | Lump.pde