PARAM, TRAKMTX

Bulk Data Entry Controls output of the mode tracking matrix during optimization.

Parameter Values Description
TRAKMTX <0, 1>
Defaults:
  • The value of this parameter is 0 if it is not included in input file.
  • If this parameter is included in the input file, but no value is provided, then running the program will result in an error.
TRAKMTX is a parameter that controls the output of the mode tracking matrix during optimization.
0 (Default)
The mode tracking matrix will not be printed to the output file.
1
The mode tracking matrix will be printed to the output file at each iteration.
The following example is of mode tracking matrix. For this example, assume that:
  1. The first 5 modes are being tracked.
  2. 10 modes are calculated for each analysis.
  3. PARAM, MFILTER is set to 0.7.

Mode Tracking Matrix:

[ 1.0 0.2 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.7 0.2 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.3 0.2 0.3 0.7 0.4 0.2 0.1 0.0 0.0 0.0 0.2 0.1 0.8 0.4 0.3 0.1 0.1 0.0 0.0 0.0 0.1 0.2 0.3 0.4 0.5 0.4 0.2 0.1 0.1 0.1 ]

Based on the above matrix, Mode 1 (of the previous iteration) will get tracked to Mode 1 (of current iteration). Mode 2 will get tracked to Mode 2. Mode 3 will get tracked to Mode 4. Mode 4 will get tracked to Mode 3. Mode 5 could not be tracked to any of the 10 modes in the current iteration (out of bounds).

Comments

  1. Each element of the mode tracking matrix stores the correlation value of two eigenvectors, which is calculated using certain mode tracking criteria (see PARAM, TRAKMETH and MODTRAK Bulk Data Entry).
  2. PARAM, MODETRAK, YES or the subcase selector MODTRAK = YES or SID should be added to the input file to activate mode tracking.