# p?lacp2

Copies all or part of a distributed matrix to another distributed matrix.

## Syntax

call pslacp2(uplo, m, n, a, ia, ja, desca, b, ib, jb, descb)

call pdlacp2(uplo, m, n, a, ia, ja, desca, b, ib, jb, descb)

call pclacp2(uplo, m, n, a, ia, ja, desca, b, ib, jb, descb)

call pzlacp2(uplo, m, n, a, ia, ja, desca, b, ib, jb, descb)

## Description

This routine copies all or part of a distributed matrix A to another distributed matrix B. No communication is performed, p?lacp2 performs a local copy sub(A):= sub(B), where sub(A) denotes `A(ia:ia+m-1`, `a:ja+n-1)` and sub(B) denotes `B(ib:ib+m-1`, `jb:jb+n-1)`.

p?lacp2 requires that only dimension of the matrix operands is distributed.

## Input Parameters

uplo

  (global) CHARACTER. Specifies the part of the distributed matrix sub(A) to be copied:

  = 'U': Upper triangular part is copied; the strictly lower triangular part of sub(A) is not referenced;

  = 'L': Lower triangular part is copied; the strictly upper triangular part of sub(A) is not referenced.

  Otherwise: all of the matrix sub(A) is copied.

m

  (global) INTEGER.

  The number of rows to be operated on, that is, the number of rows of the distributed submatrix sub(A). `(m ≥ 0)`.

n

  (global) INTEGER.

  The number of columns to be operated on, that is, the number of columns of the distributed submatrix sub(A). `(n ≥ 0)`.

a

  (local).

  REAL for pslacp2

  DOUBLE PRECISION for pdlacp2

  COMPLEX for pclacp2

  COMPLEX*16 for pzlacp2.

  Pointer into the local memory to an array of DIMENSION`(lld_a, LOCc(ja+n-1))`.

  On entry, this array contains the local pieces of the m-by-n distributed matrix sub(A).

ia, ja

  (global) INTEGER. The row and column indices in the global array A indicating the first row and the first column of sub(A), respectively.

desca

  (global and local) INTEGER array, DIMENSION (dlen_). The array descriptor for the distributed matrix A.

ib, jb

  (global) INTEGER. The row and column indices in the global array B indicating the first row and the first column of sub(B), respectively.

descb

  (global and local) INTEGER array, DIMENSION (dlen_). The array descriptor for the distributed matrix B.

## Output Parameters

b

  (local).

  REAL for pslacp2

  DOUBLE PRECISION for pdlacp2

  COMPLEX for pclacp2

  COMPLEX*16 for pzlacp2.

  Pointer into the local memory to an array of DIMENSION (lld_b, LOCc(jb+n-1) ). This array contains on exit the local pieces of the distributed matrix sub( B ) set as follows:

  if `uplo = 'U'`, B(ib+i-1, jb+j-1) = A(ia+i-1, ja+j-1), 1 ≤ i ≤ j, 1 ≤ j ≤ n;

  if `uplo = 'L'`, B(ib+i-1, jb+j-1) = A(ia+i-1, ja+j-1), j ≤ i ≤ m, 1≤ j ≤ n;

  otherwise, B(ib+i-1, jb+j-1) = A(ia+i-1, ja+j-1), 1 ≤ i ≤ m, 1 ≤ j ≤ n.

Parent topic: Auxiliary Routines