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sgeql2.f(3)				      LAPACK				      sgeql2.f(3)

       sgeql2.f -

       subroutine sgeql2 (M, N, A, LDA, TAU, WORK, INFO)
	   SGEQL2 computes the QL factorization of a general rectangular matrix using an
	   unblocked algorithm.

Function/Subroutine Documentation
   subroutine sgeql2 (integerM, integerN, real, dimension( lda, * )A, integerLDA, real,
       dimension( * )TAU, real, dimension( * )WORK, integerINFO)
       SGEQL2 computes the QL factorization of a general rectangular matrix using an unblocked


	    SGEQL2 computes a QL factorization of a real m by n matrix A:
	    A = Q * L.


		     M is INTEGER
		     The number of rows of the matrix A.  M >= 0.


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


		     A is REAL array, dimension (LDA,N)
		     On entry, the m by n matrix A.
		     On exit, if m >= n, the lower triangle of the subarray
		     A(m-n+1:m,1:n) contains the n by n lower triangular matrix L;
		     if m <= n, the elements on and below the (n-m)-th
		     superdiagonal contain the m by n lower trapezoidal matrix L;
		     the remaining elements, with the array TAU, represent the
		     orthogonal matrix Q as a product of elementary reflectors
		     (see Further Details).


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


		     TAU is REAL array, dimension (min(M,N))
		     The scalar factors of the elementary reflectors (see Further


		     WORK is REAL array, dimension (N)


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

	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

	   September 2012

       Further Details:

	     The matrix Q is represented as a product of elementary reflectors

		Q = H(k) . . . H(2) H(1), where k = min(m,n).

	     Each H(i) has the form

		H(i) = I - tau * v * v**T

	     where tau is a real scalar, and v is a real vector with
	     v(m-k+i+1:m) = 0 and v(m-k+i) = 1; v(1:m-k+i-1) is stored on exit in
	     A(1:m-k+i-1,n-k+i), and tau in TAU(i).

       Definition at line 124 of file sgeql2.f.

       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2				 Tue Sep 25 2012			      sgeql2.f(3)
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