Linear Algorithm

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This command is used to construct a Linear algorithm object which takes one iteration to solve the system of equations.

<math> \Delta U = - K^{-1}R(U),\!</math>

algorithm Linear <-initial> <-factorOnce>

-secant	optional flag to indicate to use secant stiffness
-initial	optional flag to indicate to use initial stiffness
-factorOnce	optional flag to indicate to only set up and factor matrix once

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NOTES 1) as the tangent matrix typically will not change during the analysis in case of an elastic system it is highly advantageous to use the -factorOnce option. Do not use this option if you have a nonlinear system and you want the tangent used to be actual tangent at time of the analysis step.

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Code Developed by: fmk