Source code for pyfem.util.kinematics

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#  This Python file is part of PyFEM, the code that accompanies the book:      #
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#    'Non-Linear Finite Element Analysis of Solids and Structures'             #
#    R. de Borst, M.A. Crisfield, J.J.C. Remmers and C.V. Verhoosel            #
#    John Wiley and Sons, 2012, ISBN 978-0470666449                            #
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#  Copyright (C) 2011-2025. The code is written in 2011-2012 by                #
#  Joris J.C. Remmers, Clemens V. Verhoosel and Rene de Borst and since        #
#  then augmented and maintained by Joris J.C. Remmers.                        #
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#     https://pyfem.readthedocs.io/                                            #	
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#     http://www.wiley.com/go/deborst                                          #
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from numpy import zeros

[docs] class Kinematics: """ Class that contains the kinematic state of a material point, i.e. strain and deformation gradient. Args: nDim (int): the number of spatial dimensions of the problem (2 or 3) nStr (int): the number of strain components (2, 3 or 6) """ def __init__( self , nDim: int , nStr: int ): self.F = zeros( shape=( nDim , nDim ) ) self.E = zeros( shape=( nDim , nDim ) ) self.strain = zeros( nStr ) self.dgdstrain = zeros( nStr ) self.g = 0.