larf - larf: apply Householder reflector

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subroutineclarf(characterside,integerm,integern,complex,dimension(*)v,integerincv,complextau,complex,dimension(ldc,*)c,integerldc,complex,dimension(*)work)CLARF applies an elementary reflector to a general rectangular matrix. Purpose: CLARF applies a complex elementary reflector H to a complex M-by-N matrix C, from either the left or the right. H is represented in the form H = I - tau * v * v**H where tau is a complex scalar and v is a complex vector. If tau = 0, then H is taken to be the unit matrix. To apply H**H (the conjugate transpose of H), supply conjg(tau) instead tau. ParametersSIDE SIDE is CHARACTER*1 = 'L': form H * C = 'R': form C * H M M is INTEGER The number of rows of the matrix C. N N is INTEGER The number of columns of the matrix C. V V is COMPLEX array, dimension (1 + (M-1)*abs(INCV)) if SIDE = 'L' or (1 + (N-1)*abs(INCV)) if SIDE = 'R' The vector v in the representation of H. V is not used if TAU = 0. INCV INCV is INTEGER The increment between elements of v. INCV <> 0. TAU TAU is COMPLEX The value tau in the representation of H. C C is COMPLEX array, dimension (LDC,N) On entry, the M-by-N matrix C. On exit, C is overwritten by the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'. LDC LDC is INTEGER The leading dimension of the array C. LDC >= max(1,M). WORK WORK is COMPLEX array, dimension (N) if SIDE = 'L' or (M) if SIDE = 'R' Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. subroutinedlarf(characterside,integerm,integern,doubleprecision,dimension(*)v,integerincv,doubleprecisiontau,doubleprecision,dimension(ldc,*)c,integerldc,doubleprecision,dimension(*)work)DLARF applies an elementary reflector to a general rectangular matrix. Purpose: DLARF applies a real elementary reflector H to a real m by n matrix C, from either the left or the right. H is represented in the form H = I - tau * v * v**T where tau is a real scalar and v is a real vector. If tau = 0, then H is taken to be the unit matrix. ParametersSIDE SIDE is CHARACTER*1 = 'L': form H * C = 'R': form C * H M M is INTEGER The number of rows of the matrix C. N N is INTEGER The number of columns of the matrix C. V V is DOUBLE PRECISION array, dimension (1 + (M-1)*abs(INCV)) if SIDE = 'L' or (1 + (N-1)*abs(INCV)) if SIDE = 'R' The vector v in the representation of H. V is not used if TAU = 0. INCV INCV is INTEGER The increment between elements of v. INCV <> 0. TAU TAU is DOUBLE PRECISION The value tau in the representation of H. C C is DOUBLE PRECISION array, dimension (LDC,N) On entry, the m by n matrix C. On exit, C is overwritten by the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'. LDC LDC is INTEGER The leading dimension of the array C. LDC >= max(1,M). WORK WORK is DOUBLE PRECISION array, dimension (N) if SIDE = 'L' or (M) if SIDE = 'R' Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. subroutinedlarf1f(characterside,integerm,integern,doubleprecision,dimension(*)v,integerincv,doubleprecisiontau,doubleprecision,dimension(ldc,*)c,integerldc,doubleprecision,dimension(*)work)DLARF1F applies an elementary reflector to a general rectangular Purpose: DLARF1F applies a real elementary reflector H to a real m by n matrix C, from either the left or the right. H is represented in the form H = I - tau * v * v**T where tau is a real scalar and v is a real vector. If tau = 0, then H is taken to be the unit matrix. ParametersSIDE SIDE is CHARACTER*1 = 'L': form H * C = 'R': form C * H M M is INTEGER The number of rows of the matrix C. N N is INTEGER The number of columns of the matrix C. V V is DOUBLE PRECISION array, dimension (1 + (M-1)*abs(INCV)) if SIDE = 'L' or (1 + (N-1)*abs(INCV)) if SIDE = 'R' The vector v in the representation of H. V is not used if TAU = 0. V(1) is not referenced or modified. INCV INCV is INTEGER The increment between elements of v. INCV <> 0. TAU TAU is DOUBLE PRECISION The value tau in the representation of H. C C is DOUBLE PRECISION array, dimension (LDC,N) On entry, the m by n matrix C. On exit, C is overwritten by the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'. LDC LDC is INTEGER The leading dimension of the array C. LDC >= max(1,M). WORK WORK is DOUBLE PRECISION array, dimension (N) if SIDE = 'L' or (M) if SIDE = 'R' Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. subroutinedlarf1l(characterside,integerm,integern,doubleprecision,dimension(*)v,integerincv,doubleprecisiontau,doubleprecision,dimension(ldc,*)c,integerldc,doubleprecision,dimension(*)work)DLARF1L applies an elementary reflector to a general rectangular Purpose: DLARF1L applies a real elementary reflector H to a real m by n matrix C, from either the left or the right. H is represented in the form H = I - tau * v * v**T where tau is a real scalar and v is a real vector. If tau = 0, then H is taken to be the unit matrix. ParametersSIDE SIDE is CHARACTER*1 = 'L': form H * C = 'R': form C * H M M is INTEGER The number of rows of the matrix C. N N is INTEGER The number of columns of the matrix C. V V is DOUBLE PRECISION array, dimension (1 + (M-1)*abs(INCV)) if SIDE = 'L' or (1 + (N-1)*abs(INCV)) if SIDE = 'R' The vector v in the representation of H. V is not used if TAU = 0. INCV INCV is INTEGER The increment between elements of v. INCV <> 0. TAU TAU is DOUBLE PRECISION The value tau in the representation of H. C C is DOUBLE PRECISION array, dimension (LDC,N) On entry, the m by n matrix C. On exit, C is overwritten by the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'. LDC LDC is INTEGER The leading dimension of the array C. LDC >= max(1,M). WORK WORK is DOUBLE PRECISION array, dimension (N) if SIDE = 'L' or (M) if SIDE = 'R' Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. subroutineslarf(characterside,integerm,integern,real,dimension(*)v,integerincv,realtau,real,dimension(ldc,*)c,integerldc,real,dimension(*)work)SLARF applies an elementary reflector to a general rectangular matrix. Purpose: SLARF applies a real elementary reflector H to a real m by n matrix C, from either the left or the right. H is represented in the form H = I - tau * v * v**T where tau is a real scalar and v is a real vector. If tau = 0, then H is taken to be the unit matrix. ParametersSIDE SIDE is CHARACTER*1 = 'L': form H * C = 'R': form C * H M M is INTEGER The number of rows of the matrix C. N N is INTEGER The number of columns of the matrix C. V V is REAL array, dimension (1 + (M-1)*abs(INCV)) if SIDE = 'L' or (1 + (N-1)*abs(INCV)) if SIDE = 'R' The vector v in the representation of H. V is not used if TAU = 0. INCV INCV is INTEGER The increment between elements of v. INCV <> 0. TAU TAU is REAL The value tau in the representation of H. C C is REAL array, dimension (LDC,N) On entry, the m by n matrix C. On exit, C is overwritten by the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'. LDC LDC is INTEGER The leading dimension of the array C. LDC >= max(1,M). WORK WORK is REAL array, dimension (N) if SIDE = 'L' or (M) if SIDE = 'R' Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. subroutinezlarf(characterside,integerm,integern,complex*16,dimension(*)v,integerincv,complex*16tau,complex*16,dimension(ldc,*)c,integerldc,complex*16,dimension(*)work)ZLARF applies an elementary reflector to a general rectangular matrix. Purpose: ZLARF applies a complex elementary reflector H to a complex M-by-N matrix C, from either the left or the right. H is represented in the form H = I - tau * v * v**H where tau is a complex scalar and v is a complex vector. If tau = 0, then H is taken to be the unit matrix. To apply H**H, supply conjg(tau) instead tau. ParametersSIDE SIDE is CHARACTER*1 = 'L': form H * C = 'R': form C * H M M is INTEGER The number of rows of the matrix C. N N is INTEGER The number of columns of the matrix C. V V is COMPLEX*16 array, dimension (1 + (M-1)*abs(INCV)) if SIDE = 'L' or (1 + (N-1)*abs(INCV)) if SIDE = 'R' The vector v in the representation of H. V is not used if TAU = 0. INCV INCV is INTEGER The increment between elements of v. INCV <> 0. TAU TAU is COMPLEX*16 The value tau in the representation of H. C C is COMPLEX*16 array, dimension (LDC,N) On entry, the M-by-N matrix C. On exit, C is overwritten by the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'. LDC LDC is INTEGER The leading dimension of the array C. LDC >= max(1,M). WORK WORK is COMPLEX*16 array, dimension (N) if SIDE = 'L' or (M) if SIDE = 'R' Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. subroutinezlarf1f(characterside,integerm,integern,complex*16,dimension(*)v,integerincv,complex*16tau,complex*16,dimension(ldc,*)c,integerldc,complex*16,dimension(*)work)ZLARF1F applies an elementary reflector to a general rectangular Purpose: ZLARF1F applies a complex elementary reflector H to a real m by n matrix C, from either the left or the right. H is represented in the form H = I - tau * v * v**H where tau is a complex scalar and v is a complex vector. If tau = 0, then H is taken to be the unit matrix. To apply H**H, supply conjg(tau) instead tau. ParametersSIDE SIDE is CHARACTER*1 = 'L': form H * C \param[in] M \verbatim M is INTEGER The number of rows of the matrix C. N N is INTEGER The number of columns of the matrix C. V V is COMPLEX*16 array, dimension (1 + (M-1)*abs(INCV)) if SIDE = 'L' or (1 + (N-1)*abs(INCV)) if SIDE = 'R' The vector v in the representation of H. V is not used if TAU = 0. V(1) is not referenced or modified. INCV INCV is INTEGER The increment between elements of v. INCV <> 0. TAU TAU is COMPLEX*16 The value tau in the representation of H. C C is COMPLEX*16 array, dimension (LDC,N) On entry, the m by n matrix C. On exit, C is overwritten by the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'. LDC LDC is INTEGER The leading dimension of the array C. LDC >= max(1,M). WORK WORK is COMPLEX*16 array, dimension (N) if SIDE = 'L' or (M) if SIDE = 'R' Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd.

larf - larf: apply Householder reflector

Functions subroutine clarf (side, m, n, v, incv, tau, c, ldc, work) CLARF applies an elementary reflector to a general rectangular matrix. subroutine dlarf (side, m, n, v, incv, tau, c, ldc, work) DLARF applies an elementary reflector to a general rectangular matrix. subroutine dlarf1f (side, m, n, v, incv, tau, c, ldc, work) DLARF1F applies an elementary reflector to a general rectangular subroutine dlarf1l (side, m, n, v, incv, tau, c, ldc, work) DLARF1L applies an elementary reflector to a general rectangular subroutine slarf (side, m, n, v, incv, tau, c, ldc, work) SLARF applies an elementary reflector to a general rectangular matrix. subroutine zlarf (side, m, n, v, incv, tau, c, ldc, work) ZLARF applies an elementary reflector to a general rectangular matrix. subroutine zlarf1f (side, m, n, v, incv, tau, c, ldc, work) ZLARF1F applies an elementary reflector to a general rectangular