la_lapack::gbequb Interface Reference

GBEQUB: computes row and column scalings intended to equilibrate an M-by-N matrix A and reduce its condition number. R returns the row scale factors and C the column scale factors, chosen to try to make the largest element in each row and column of the matrix B with elements B(i,j)=R(i)*A(i,j)*C(j) have an absolute value of at most the radix. R(i) and C(j) are restricted to be a power of the radix between SMLNUM = smallest safe number and BIGNUM = largest safe number. Use of these scaling factors is not guaranteed to reduce the condition number of A but works well in practice. This routine differs from CGEEQU by restricting the scaling factors to a power of the radix. Barring over- and underflow, scaling by these factors introduces no additional rounding errors. However, the scaled entries' magnitudes are no longer approximately 1 but lie between sqrt(radix) and 1/sqrt(radix). More...

Public Member Functions
pure subroutine	cgbequb (m, n, kl, ku, ab, ldab, r, c, rowcnd, colcnd, amax, info)
	la_cgbequb
pure subroutine	dgbequb (m, n, kl, ku, ab, ldab, r, c, rowcnd, colcnd, amax, info)
	la_dgbequb
	la_qgbequb
pure subroutine	sgbequb (m, n, kl, ku, ab, ldab, r, c, rowcnd, colcnd, amax, info)
	la_sgbequb
	la_wgbequb
pure subroutine	zgbequb (m, n, kl, ku, ab, ldab, r, c, rowcnd, colcnd, amax, info)
	la_zgbequb

Detailed Description

GBEQUB: computes row and column scalings intended to equilibrate an M-by-N matrix A and reduce its condition number. R returns the row scale factors and C the column scale factors, chosen to try to make the largest element in each row and column of the matrix B with elements B(i,j)=R(i)*A(i,j)*C(j) have an absolute value of at most the radix. R(i) and C(j) are restricted to be a power of the radix between SMLNUM = smallest safe number and BIGNUM = largest safe number. Use of these scaling factors is not guaranteed to reduce the condition number of A but works well in practice. This routine differs from CGEEQU by restricting the scaling factors to a power of the radix. Barring over- and underflow, scaling by these factors introduces no additional rounding errors. However, the scaled entries' magnitudes are no longer approximately 1 but lie between sqrt(radix) and 1/sqrt(radix).

Member Function/Subroutine Documentation

cgbequb()

pure subroutine la_lapack::gbequb::cgbequb	(	integer(ilp), intent(in)	m,
		integer(ilp), intent(in)	n,
		integer(ilp), intent(in)	kl,
		integer(ilp), intent(in)	ku,
		complex(sp), dimension(ldab,*), intent(in)	ab,
		integer(ilp), intent(in)	ldab,
		real(sp), dimension(*), intent(out)	r,
		real(sp), dimension(*), intent(out)	c,
		real(sp), intent(out)	rowcnd,
		real(sp), intent(out)	colcnd,
		real(sp), intent(out)	amax,
		integer(ilp), intent(out)	info
	)

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dgbequb()

pure subroutine la_lapack::gbequb::dgbequb	(	integer(ilp), intent(in)	m,
		integer(ilp), intent(in)	n,
		integer(ilp), intent(in)	kl,
		integer(ilp), intent(in)	ku,
		real(dp), dimension(ldab,*), intent(in)	ab,
		integer(ilp), intent(in)	ldab,
		real(dp), dimension(*), intent(out)	r,
		real(dp), dimension(*), intent(out)	c,
		real(dp), intent(out)	rowcnd,
		real(dp), intent(out)	colcnd,
		real(dp), intent(out)	amax,
		integer(ilp), intent(out)	info
	)

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la_cgbequb()

la_lapack::gbequb::la_cgbequb

la_dgbequb()

la_lapack::gbequb::la_dgbequb

la_qgbequb()

la_lapack::gbequb::la_qgbequb

la_sgbequb()

la_lapack::gbequb::la_sgbequb

la_wgbequb()

la_lapack::gbequb::la_wgbequb

la_zgbequb()

la_lapack::gbequb::la_zgbequb

sgbequb()

pure subroutine la_lapack::gbequb::sgbequb	(	integer(ilp), intent(in)	m,
		integer(ilp), intent(in)	n,
		integer(ilp), intent(in)	kl,
		integer(ilp), intent(in)	ku,
		real(sp), dimension(ldab,*), intent(in)	ab,
		integer(ilp), intent(in)	ldab,
		real(sp), dimension(*), intent(out)	r,
		real(sp), dimension(*), intent(out)	c,
		real(sp), intent(out)	rowcnd,
		real(sp), intent(out)	colcnd,
		real(sp), intent(out)	amax,
		integer(ilp), intent(out)	info
	)

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zgbequb()

pure subroutine la_lapack::gbequb::zgbequb	(	integer(ilp), intent(in)	m,
		integer(ilp), intent(in)	n,
		integer(ilp), intent(in)	kl,
		integer(ilp), intent(in)	ku,
		complex(dp), dimension(ldab,*), intent(in)	ab,
		integer(ilp), intent(in)	ldab,
		real(dp), dimension(*), intent(out)	r,
		real(dp), dimension(*), intent(out)	c,
		real(dp), intent(out)	rowcnd,
		real(dp), intent(out)	colcnd,
		real(dp), intent(out)	amax,
		integer(ilp), intent(out)	info
	)

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The documentation for this interface was generated from the following file:

• la_lapack.f90