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1.2 Changing the finite element type

Module NOP2P1 converts a NOPO data structure containing P2 elements into a structure composed of P1 elements only. In practice, the module splits triangular P2 elements into 4 P1 triangles (the point coordinates on the edges are calculated at the center of these edges).

 

      SUBROUTINE NOP2P1(M,NFNOP1,NINOP1,NFNOP2,NINOP2)
C ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
C AIM : GEOMETRIC TRANSFORMATION OF A P2 D.S. NOPO INTO A P1 D.S. NOPO
C  +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

where

• M is the super array,
• NFNOP1, NINOP1 are the file number and level of the input D.S. NOPO,
• NFNOP2, NINOP2 are the file number and level of the output D.S. NOPO.

An analogous module, NOQ2Q1 converts Q2 elements with 9 nodes to Q1 elements.

      SUBROUTINE NOQ2Q1(M,NFNOP1,NINOP1,NFNOP2,NINOP2)
C ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
C AIM : GEOMETRIC TRANSFORMATION OF A Q2 D.S. NOPO INTO A Q1 D.S. NOPO
C ---   (Q2 WITH 9 NODES ONLY)
C  +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Module NOTRP1 converts a NOPO data structure containing triangular elements with 7 nodes into a structure composed of P1 elements only. In practice, the module splits the initial triangles into 6 P1 triangles.

       SUBROUTINE NOTRP1(M,NFNOP1,NINOP1,NFNOP2,NINOP2)
C ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
C AIM : GEOMETRIC TRANSFORMATION OF A D.S. NOPO CONTAINING RUAS
C ---   TRIANGLES WITH 7 NODES INTO A P1 D.S. NOPO
C  +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

where

• M is the super array,
• NFNOP1, NINOP1 are the file number and level of the input D.S. NOPO,
• NFNOP2, NINOP2 are the file number and level of the output D.S. NOPO.