1DSFRK(1)LAPACK routine (version 3.2)                                  DSFRK(1)
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NAME

6       DSFRK - 3 BLAS like routine for C in RFP Format
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SYNOPSIS

9       SUBROUTINE DSFRK( TRANSR, UPLO, TRANS, N, K, ALPHA, A, LDA, BETA,
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11           +             C )
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13           DOUBLE        PRECISION ALPHA, BETA
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15           INTEGER       K, LDA, N
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17           CHARACTER     TRANS, TRANSR, UPLO
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19           DOUBLE        PRECISION A( LDA, * ), C( * )
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PURPOSE

22       Level  3  BLAS like routine for C in RFP Format.  DSFRK performs one of
23       the symmetric rank--k operations
24          C := alpha*A*A' + beta*C,
25       or
26          C := alpha*A'*A + beta*C,
27       where alpha and beta are real  scalars,  C  is  an  n--by--n  symmetric
28       matrix  and  A  is  an n--by--k matrix in the first case and a k--by--n
29       matrix in the second case.
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ARGUMENTS

32       TRANSR    (input) CHARACTER
33                 = 'N':  The Normal Form of RFP A is stored;
34                 = 'T':  The Transpose Form of RFP A is stored.
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36       UPLO   - (input) CHARACTER
37              On  entry, UPLO specifies whether the upper or lower  triangular
38              part  of  the array C is to be referenced as follows: UPLO = 'U'
39              or 'u'   Only the upper triangular part of C  is  to  be  refer‐
40              enced.   UPLO = 'L' or 'l'   Only the lower triangular part of C
41              is to be referenced.  Unchanged on exit.
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43       TRANS  - (input) CHARACTER
44              On entry, TRANS specifies the operation to be performed as  fol‐
45              lows:  TRANS  =  'N' or 'n'   C := alpha*A*A' + beta*C.  TRANS =
46              'T' or 't'   C := alpha*A'*A + beta*C.  Unchanged on exit.
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48       N      - (input) INTEGER.
49              On entry, N specifies the order of the matrix C. N  must  be  at
50              least zero.  Unchanged on exit.
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52       K      - (input) INTEGER.
53              On  entry  with  TRANS  =  'N' or 'n', K specifies the number of
54              columns of the matrix A, and on entry with TRANS = 'T' or 't', K
55              specifies the number of rows of the matrix A. K must be at least
56              zero.  Unchanged on exit.
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58       ALPHA  - (input) DOUBLE PRECISION.
59              On entry, ALPHA specifies the scalar alpha.  Unchanged on exit.
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61       A      - (input) DOUBLE PRECISION array of DIMENSION ( LDA, ka ), where
62       KA
63              is  K  when TRANS = 'N' or 'n', and is N otherwise. Before entry
64              with TRANS = 'N' or 'n', the leading N--by--K part of the  array
65              A must contain the matrix A, otherwise the leading K--by--N part
66              of the array A must contain the matrix A.  Unchanged on exit.
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68       LDA    - (input) INTEGER.
69              On entry, LDA specifies the first dimension of A as declared  in
70              the   calling   (sub)   program.   When  TRANS = 'N' or 'n' then
71              LDA must be at least  max( 1, n ), otherwise   LDA  must  be  at
72              least  max( 1, k ).  Unchanged on exit.
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74       BETA   - (input) DOUBLE PRECISION.
75              On entry, BETA specifies the scalar beta.  Unchanged on exit.
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77       C      - (input/output) DOUBLE PRECISION array, dimension ( NT );
78              NT  = N*(N+1)/2. On entry, the symmetric matrix C in RFP Format.
79              RFP Format is described by TRANSR, UPLO and N.
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ARGUMENTS

82 LAPACK routine (version 3.2)    November 2008                        DSFRK(1)
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