SysTutorials

Linux Manual Pages › Section 3

ctfttr(3)

NAME

ctfttr.f –

SYNOPSIS

Functions/Subroutines

subroutine ctfttr (TRANSR, UPLO, N, ARF, A, LDA, INFO)
CTFTTR copies a triangular matrix from the rectangular full packed format (TF) to the standard full format (TR).

Function/Subroutine Documentation

subroutine ctfttr (characterTRANSR, characterUPLO, integerN, complex, dimension( 0: * )ARF, complex, dimension( 0: lda-1, 0: * )A, integerLDA, integerINFO)

CTFTTR copies a triangular matrix from the rectangular full packed format (TF) to the standard full format (TR).

Purpose:

 CTFTTR copies a triangular matrix A from rectangular full packed
 format (TF) to standard full format (TR).

 

Parameters:

TRANSR

          TRANSR is CHARACTER*1
          = 'N':  ARF is in Normal format;
          = 'C':  ARF is in Conjugate-transpose format;

UPLO

          UPLO is CHARACTER*1
          = 'U':  A is upper triangular;
          = 'L':  A is lower triangular.

N

          N is INTEGER
          The order of the matrix A.  N >= 0.

ARF

          ARF is COMPLEX array, dimension ( N*(N+1)/2 ),
          On entry, the upper or lower triangular matrix A stored in
          RFP format. For a further discussion see Notes below.

A

          A is COMPLEX array, dimension ( LDA, N )
          On exit, the triangular matrix A.  If UPLO = 'U', the
          leading N-by-N upper triangular part of the array A contains
          the upper triangular matrix, and the strictly lower
          triangular part of A is not referenced.  If UPLO = 'L', the
          leading N-by-N lower triangular part of the array A contains
          the lower triangular matrix, and the strictly upper
          triangular part of A is not referenced.

LDA

          LDA is INTEGER
          The leading dimension of the array A.  LDA >= max(1,N).

INFO

          INFO is INTEGER
          = 0:  successful exit
          < 0:  if INFO = -i, the i-th argument had an illegal value

 

Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

September 2012

Further Details:


We first consider Standard Packed Format when N is even.We give an example where N = 6. AP is Upper AP is Lower 00 01 02 03 04 05 00 11 12 13 14 15 10 11 22 23 24 25 20 21 22 33 34 35 30 31 32 33 44 45 40 41 42 43 44 55 50 51 52 53 54 55 Let TRANSR = 'N'.RFP holds AP as follows : For UPLO = 'U' the upper trapezoid A(0 : 5, 0 : 2) consists of the last
                                                                                                                                                                                                                                                                                                        three columns of AP upper.The lower triangle A(4 : 6, 0 : 2) consists of
                                                                                                                                                                                                                                                                                                            conjugate -
                                                                                                                                                                                                                                                                                                    transpose of the first three columns of AP upper.For UPLO = 'L' the lower trapezoid A(1 : 6, 0 : 2) consists of the first
                                                                                                                                                                                                                                                                                                                                                                    three columns of AP lower.The upper triangle A(0 : 2, 0 : 2) consists of
                                                                                                                                                                                                                                                                                                                                                                        conjugate -
                                                                                                                                                                                                                                                                                                                                                                transpose of the last three columns of AP lower.To denote conjugate we place-- above the element.This covers the case N even and TRANSR = 'N'.RFP A RFP A-- -- --03 04 05 33 43 53 -- --13 14 15 00 44 54 --23 24 25 10 11 55 33 34 35 20 21 22 --00 44 45 30 31 32 -- --01 11 55 40 41 42 -- -- --02 12 22 50 51 52 Now let TRANSR = 'C'.RFP A in both UPLO cases is just the conjugate -
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      transpose of RFP A above.One therefore gets : RFP A RFP A-- -- -- -- -- -- -- -- -- --03 13 23 33 00 01 02 33 00 10 20 30 40 50 -- -- -- -- -- -- -- -- -- --04 14 24 34 44 11 12 43 44 11 21 31 41 51 -- -- -- -- -- -- -- -- -- --05 15 25 35 45 55 22 53 54 55 22 32 42 52 We next consider Standard Packed Format when N is odd.We give an example where N = 5. AP is Upper AP is Lower 00 01 02 03 04 00 11 12 13 14 10 11 22 23 24 20 21 22 33 34 30 31 32 33 44 40 41 42 43 44 Let TRANSR = 'N'.RFP holds AP as follows : For UPLO = 'U' the upper trapezoid A(0 : 4, 0 : 2) consists of the last
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      three columns of AP upper.The lower triangle A(3 : 4, 0 : 1) consists of
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          conjugate -
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  transpose of the first two columns of AP upper.For UPLO = 'L' the lower trapezoid A(0 : 4, 0 : 2) consists of the first
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                three columns of AP lower.The upper triangle A(0 : 1, 1 : 2) consists of
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    conjugate -
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            transpose of the last two columns of AP lower.To denote conjugate we place-- above the element.This covers the case N odd and TRANSR = 'N'.RFP A RFP A-- --02 03 04 00 33 43 --12 13 14 10 11 44 22 23 24 20 21 22 --00 33 34 30 31 32 -- --01 11 44 40 41 42 Now let TRANSR = 'C'.RFP A in both UPLO cases is just the conjugate -
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           transpose of RFP A above.One therefore gets : RFP A RFP A-- -- -- -- -- -- -- -- --02 12 22 00 01 00 10 20 30 40 50 -- -- -- -- -- -- -- -- --03 13 23 33 11 33 11 21 31 41 51 -- -- -- -- -- -- -- -- --04 14 24 34 44 43 44 22 32 42 52

 

Definition at line 217 of file ctfttr.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Index