# VECFEM3 Reference Manual: vemu05

Type: FORTRAN routine

## NAME

vemu05 - evaluation of a function C at the geometrical nodes

## SYNOPSIS

CALL VEMU05(
  T, LCU, CU, LU, U, LIVEM, IVEM, LNEK, NEK, LRPARM, RPARM, LIPARM, IPARM, LDNOD, DNOD, LRDPRM, RDPARM, LIDPRM, IDPARM, LNODN, NODNUM, LNOD, NOD, LNOPRM, NOPARM, LBIG, RBIG, IBIG, USERC)
INTEGER
  LCU, LU, LIVEM, LNEK, LRPARM, LIPARM, LDNOD, LRDPRM, LIDPRM, LNODN, LNOPRM, LBIG
INTEGER
  IVEM(LIVEM), NEK(LNEK), IPARM(LIPARM), DNOD(LDNOD), IDPARM(LIDPRM), NODNUM(LNODN), IBIG(*)
DOUBLE PRECISION
  T, CU(LCU), U(LU), RPARM(LRPARM), RDPARM(LRDPRM), NOD(LDNOD), NOPARM(LNOPRM), RBIG(LBIG)
EXTERNAL
  USERC

## PURPOSE

vemu05 is a routine to compute a NC-valued function C at the geometrical nodes of the finite element mesh. It works for isoparametrical meshes and for the element libraries PRFLIB=0 and PRFLIB=1. C depends on the location and the NK-valued input solution U and its derivative. U is given at the global nodes of the FEM mesh. vemu05 can be used to interpolate a solution given on the global nodes onto the geometrical nodes. The results can be handed over to a standard postprocessor which processes nodal results (see veid97, vepa97).

## ARGUMENTS

T double precision, scalar, input, global
  Real number (e.g. current time).
LCU integer, scalar, input, local
  Length of vector CU, LCU>=NC*CU1.
CU double precision, array: CU(LCU), output, local
  The values of the function C at the geometrical nodes on the process MYPROC. CU(CU1*(j-1)+i) is the value of the j-th component of C at the geometrical node i, where i refers to the local numbering on the process. Since the function C is only evaluated for inner elements it may happen that a geometrical node gets no contribution from the evaluation process and CU is undefined at this node. vemu05 sets these entries to the alternative value 10.D0**IVEM(4).
LU integer, scalar, input, local
  Length of solution vector U, LU >=LM.
U double precision, array: U(LU), input, local
  The input solution vector at the global nodes. U(i) is the value of the input solution at the global node i+PTRMBK(MYPROC), see vemdis.
LIVEM integer, scalar, input, local
  Length of the integer information vector, LIVEM>= MESH+ NINFO.
IVEM integer, array: IVEM(LIVEM), input/output, local/global
  Integer information vector.
  (1)=MESH, input, local
    Start address of the mesh informations in IVEM, MESH>203+ NPROC.
  (2)=ERR, output, global
    Error number.

    0 | program terminated without error.
    90 | LBIG is too small.
    95 | IVEM, U or CU is too small.
    99 | fatal error.

  (4), input, global
    For unreferenced geometrical nodes CU is set to 10.D0**IVEM(4), normally 40.
  (5)=NIVEM, output, local
    Used length of IVEM.
  (30)=LOUT, input, local
    Unit number of the standard output file, normally 6.
  (31)=OUTCNT, input, local
    Output control flag.

    0 | only error messages are printed.
    >0 | in addition a protocol is printed.

  (32)=CU1, input, local
    Leading dimension of the nodal value array CU, CU1>=NDEG. If CU1<NDEG, CU1 is set to NDEG.
  (33)=NC, input, global
    Number of components of function C.
  (200)=NPROC, input, global
    Number of processes, see combgn.
  (201)=MYPROC, input, local
    Logical process id number, see combgn.
  (202)=NMSG, input/output, global
    Message counter. The difference of the input and the output values gives the number of communications during the vemu05 call.
  (204)=TIDS(1), input, global
    Begin of the list TIDS which defines the mapping of the logical process ids to the physical process ids. See combgn.
  (MESH), input, local
    Start of mesh informations, see mesh.
LNEK integer, scalar, input, local
  Length of the element array.
NEK integer, array: NEK(LNEK), input, local
  Array of the elements, see mesh.
LRPARM integer, scalar, input, local
  Length of the real parameter array.
RPARM double precision, array: RPARM(LRPARM), input, local
  Real parameter array, see mesh.
LIPARM integer, scalar, input, local
  Length of the integer parameter array.
IPARM integer, array: IPARM(LIPARM), input, local
  Integer parameter array, see mesh.
LDNOD integer, scalar, input, local
  Length of the array of the Dirichlet nodes.
DNOD integer, array: DNOD(LDNOD), input, local
  Array of the Dirichlet nodes, see mesh.
LRDPRM integer, scalar, input, local
  Length of the real Dirichlet parameter array.
RDPARM double precision, array: RDPARM(LRDPRM), input, local
  Array of the real Dirichlet parameters, see mesh.
LIDPRM integer, scalar, input, local
  Length of the integer Dirichlet parameter array.
IDPARM integer, array: IDPARM(LIDPRM), input, local
  Array of the integer Dirichlet parameters, see mesh.
LNODN integer, scalar, input, local
  Length of the array of the id numbers of the geometrical nodes.
NODNUM integer, array: NODNUM(LNODN), input, local
  Array of the id numbers of the geometrical nodes, see mesh.
LNOD integer, scalar, input, local
  Length of the array of the coordinates of the geometrical nodes.
NOD double precision, array: NOD(LNOD), input, local
  Array of the coordinates of the geometrical nodes, see mesh.
LNOPRM integer, scalar, input, local
  Length of the array of the node parameters.
NOPARM double precision, array: NOPARM(LNOPRM), input, local
  Array of the node parameters, see mesh.
LBIG integer, scalar, input, local
  Length of the real work array. The needed length of LBIG depends on the given mesh. A minimal length of LBIG cannot be given. It should be as large as possible.
RBIG double precision, array: RBIG(LBIG), work array, local
  Real work array.
IBIG integer, array: IBIG(*), work array, local
  Integer work array, RBIG and IBIG have to be defined by the EQUIVALENCE statement.
USERC external
  Name of the subroutine in which the function C is described, see userc.

## EXAMPLE

See vemexamples.

## METHOD

The value of the function C at a geometrical node is the arithmetic mean of all evaluations of C on all inner elements containing this geometrical node. Geometrical nodes contained in no inner element get the value 10.D0**IVEM(4). To compute the values of U and its derivatives at a geometrical node, the values of U at the global nodes are interpolated by a polynomial.

## REFERENCES

[FAQ], [DATAMAN], [DATAMAN2], [P_MPI].

## SEE ALSO

VECFEM, vemcompile, vemrun, vemhint, mesh, vemexamples, vemdis, userc, vemu03, vemu04, vemu06, vemu07, vemu13.

## COPYRIGHTS

Program by L. Grosz, C. Roll, P. Sternecker, 1989-1996. Copyrights by Universitaet Karlsruhe 1989-1996. Copyrights by Lutz Grosz 1996. All rights reserved. More details see VECFEM.

by L. Grosz, Auckland , 6. June, 2000.