# FreeBSD Manual Pages

PZLACGV(l) ) PZLACGV(l)NAMEPZLACGV - conjugate a complex vector of length N, sub( X ), where sub( X ) denotes X(IX,JX:JX+N-1) if INCX = DESCX( M_ ) and X(IX:IX+N-1,JX) if INCX = 1, and Notes ===== Each global data object is described by an associated description vectorSYNOPSISSUBROUTINE PZLACGV( N, X, IX, JX, DESCX, INCX ) INTEGER INCX, IX, JX, N INTEGER DESCX( * ) COMPLEX*16 X( * )PURPOSEPZLACGV conjugates a complex vector of length N, sub( X ), where sub( X ) denotes X(IX,JX:JX+N-1) if INCX = DESCX( M_ ) and X(IX:IX+N-1,JX) if INCX = 1, and Notes ===== Each global data object is described by an associated description vector. This vector stores the information re- quired to establish the mapping between an object element and its cor- responding process and memory location. Let A be a generic term for any 2D block cyclicly distributed array. Such a global array has an associated description vector DESCA. In the following comments, the character _ should be read as "of the global array". NOTATION STORED IN EXPLANATION --------------- -------------- -------------------------------------- DTYPE_A(global) DESCA( DTYPE_ )The descriptor type. In this case, DTYPE_A = 1. CTXT_A (global) DESCA( CTXT_ ) The BLACS context handle, indicating the BLACS process grid A is distribu- ted over. The context itself is glo- bal, but the handle (the integer value) may vary. M_A (global) DESCA( M_ ) The number of rows in the global array A. N_A (global) DESCA( N_ ) The number of columns in the global array A. MB_A (global) DESCA( MB_ ) The blocking factor used to distribute the rows of the array. NB_A (global) DESCA( NB_ ) The blocking factor used to distribute the columns of the array. RSRC_A (global) DESCA( RSRC_ ) The process row over which the first row of the array A is distributed. CSRC_A (global) DESCA( CSRC_ ) The process column over which the first column of the array A is distributed. LLD_A (local) DESCA( LLD_ ) The leading dimension of the local array. LLD_A >= MAX(1,LOCr(M_A)). Let K be the number of rows or columns of a distributed matrix, and as- sume that its process grid has dimension p x q. LOCr( K ) denotes the number of elements of K that a process would re- ceive if K were distributed over the p processes of its process column. Similarly, LOCc( K ) denotes the number of elements of K that a process would receive if K were distributed over the q processes of its process row. The values of LOCr() and LOCc() may be determined via a call to the ScaLAPACK tool function, NUMROC: LOCr( M ) = NUMROC( M, MB_A, MYROW, RSRC_A, NPROW ), LOCc( N ) = NUMROC( N, NB_A, MYCOL, CSRC_A, NPCOL ). An upper bound for these quantities may be computed by: LOCr( M ) <= ceil( ceil(M/MB_A)/NPROW )*MB_A LOCc( N ) <= ceil( ceil(N/NB_A)/NPCOL )*NB_A Because vectors may be viewed as a subclass of matrices, a distributed vector is considered to be a distributed matrix.ARGUMENTSN (global input) INTEGER The length of the distributed vector sub( X ). X (local input/local output) COMPLEX*16 pointer into the local memory to an array of dimension (LLD_X,*). On entry the vector to be conjugated x( i ) = X(IX+(JX-1)*M_X +(i-1)*INCX ), 1 <= i <= N. On exit the conjugated vector. IX (global input) INTEGER The row index in the global array X indicating the first row of sub( X ). JX (global input) INTEGER The column index in the global array X indicating the first column of sub( X ). DESCX (global and local input) INTEGER array of dimension DLEN_. The array descriptor for the distributed matrix X. INCX (global input) INTEGER The global increment for the elements of X. Only two values of INCX are supported in this version, namely 1 and M_X. INCX must not be zero. ScaLAPACK version 1.7 13 August 2001 PZLACGV(l)

NAME | SYNOPSIS | PURPOSE | ARGUMENTS

Want to link to this manual page? Use this URL:

<https://www.freebsd.org/cgi/man.cgi?query=pzlacgv&manpath=FreeBSD+12.1-RELEASE+and+Ports>