# PetIGA / demo / Elasticity.c

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144``` ```/* This code solves the 3D elasticity equations given the Lame constants and subject to Dirichlet and Neumann boundary conditions. keywords: steady, vector, linear */ #include "petiga.h" #if PETSC_VERSION_LT(3,5,0) #define KSPSetOperators(ksp,A,B) KSPSetOperators(ksp,A,B,SAME_NONZERO_PATTERN) #endif typedef struct { PetscReal mu; PetscReal lambda; } AppCtx; PETSC_STATIC_INLINE PetscReal DOT(PetscInt dim,const PetscReal a[],const PetscReal b[]) { PetscInt i; PetscReal s = 0.0; for (i=0; imu; PetscReal lambda = user->lambda; PetscInt a,b,nen = p->nen; PetscInt i,j,dim = p->dim; PetscReal (*B) = (typeof(B)) p->shape[0]; PetscReal (*D)[dim] = (typeof(D)) p->shape[1]; PetscScalar (*K)[dim][nen][dim] = (typeof(K)) KK; PetscScalar (*F)[dim] = (typeof(F)) FF; for (a=0; a