*HEADING
 SUBSTRUCTURE GENERATION FILE
*NODE,NSET="ALL NODES"
*NGEN,NSET="ALL NODES"
** ----------------------- Element
*ELEMENT,TYPE=B21,ELSET="BEAM ELEMENTS"
*ELGEN,ELSET="BEAM ELEMENTS"
*BEAMSECTION,ELSET="BEAM ELEMENTS",SECT=RECT,MAT=STEEL
*MATERIAL,NAME=STEEL
*ELASTIC
 2.1E11,0.3
*DENSITY
 7800.,
**
*NSET,NSET=RETNODES
**
**
*STEP
*FREQUENCY,EIGENSOLVER=LANCZOS
 6,,
*BOUNDARY
  1,1,2
  1,6,6
  RETNODES, 1, 2
*NODE PRINT,NSET="ALL NODES"
U,
*NODE FILE,NSET="ALL NODES"
U,
*END STEP
**
**
**
*step
*SUBSTRUCTURE GENERATE,TYPE=Z1,RECOVERYMATRIX=YES,MASSMATRIX=YES,OVERWRITE
*RETAINED NODAL DOFS
 RETNODES,1,2
*RETAINED EIGENMODES,GENERATE
*BOUNDARY
  1,1,2
  1,6,6
**
*SUBSTRUCTURE MATRIX OUTPUT,STIFFNESS=YES,MASS=YES,SLOAD=YES,
RECOVERYMATRIX=YES,FILENAME=MATRIXNEW
*END STEP