eigen

Mapdl.eigen(kmatrix='', mmatrix='', cmatrix='', evals='', evects='', **kwargs)

Performs a modal solution with unsymmetric or damping matrices.

APDL Command: *EIGEN

Parameters
  • kmatrix – Name of the stiffness matrix. May be a real or complex-valued matrix.

  • mmatrix – Name of the mass matrix.

  • cmatrix – Name of the damping matrix (used only for MODOPT,DAMP).

  • evals – Name of the output eigenvalues vector. It will be an m-long *VEC vector of complex values, where m is the number of eigenvalues requested (MODOPT).

  • evects – Name of the output eigenvector matrix. It will be a n x m *DMAT (dense) matrix of complex values, where n is the size of the matrix and m is the number of eigenvalues requested (MODOPT).

Notes

Use the command ANTYPE,MODAL and the MODOPT command to specify the modal solution options. Only MODOPT,DAMP, MODOPT,UNSYM, MODOPT,LANB, and MODOPT,SUBSP are supported.

*EIGEN with Block Lanczos (LANB) only supports sparse matrices.

Distributed ANSYS Restriction: This command is not supported in Distributed ANSYS.