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Next: 6.6 NRPLWVNPLINI parameter Up: 6 The param.inc file Previous: 6.4 NTYPDNIOND, NKDIM

6.5 NBLK, MCPU parameter

 

These flags should be set according to the computer on which VASP runs.

In some cases VASP has to perform an unitary transformation of the current wave functions. This is done using a work array CBLOCK and the following FORTRAN code:

      DO 100 IBLOCK=0,NPL-1,NBLK
      ILEN=MIN(NBLK,NPL-IBLOCK)

      DO 200 N1=1,N
      DO 200 M=1,ILEN
          CBLOCK(M,N1)=C(M+IBLOCK,N1)
          C(M+IBLOCK,N1)=0
  200 CONTINUE

C     C(IBLOCK+I,N)=SUM_(J,K) CH(I,K) CBLOCK(K,N)
      CALL ZGEMM ('N', 'N', ILEN, N, N, (1.,0.), CBLOCK, NBLK, CH, N,
     &   (1.,0.), C(IBLOCK+1,1), NDIM)
  100 CONTINUE
ZGEMM is the matrix tex2html_wrap_inline4401 matrix multiplication command of the BLAS package. The task performed by this call is indicated by the comment line written above the ZGEMM call. Generally NBLK=16 or 32 is large enough for super-scalar machines. A large value might be necessary on vector machines for optimal performance (NBLK=128). (In VASP.4.X. NBLK is can be read from the INCAR file during run time).

MCPU is not supported.



MASTER USER VASP
Mon Mar 29 10:38:29 MEST 1999