Chapter 3: Frequency Domain Decomposition for Modal Analyses

Use the Block Lanczos eigensolver in conjunction with frequency domain decomposition (DDOPT,FREQ) to compute all of the mode shapes. Frequency domain decomposition significantly improves the efficiency of the parallel computations. Use this feature only when seeking 500 or more mode shapes and when a sufficient amount of memory is available.

For information on DMP output file handling, see Differences in General Behavior in the Parallel Processing Guide.