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<HTML>
<HEAD><TITLE>MB01QD - SLICOT Library Routine Documentation</TITLE>
</HEAD>
<BODY>

<H2><A Name="MB01QD">MB01QD</A></H2>
<H3>
Matrix scaling (lower level routine)
</H3>
<A HREF ="#Specification"><B>[Specification]</B></A>
<A HREF ="#Arguments"><B>[Arguments]</B></A>
<A HREF ="#Method"><B>[Method]</B></A>
<A HREF ="#References"><B>[References]</B></A>
<A HREF ="#Comments"><B>[Comments]</B></A>
<A HREF ="#Example"><B>[Example]</B></A>

<P>
<B><FONT SIZE="+1">Purpose</FONT></B>
<PRE>
  To multiply the M by N real matrix A by the real scalar CTO/CFROM.
  This is done without over/underflow as long as the final result
  CTO*A(I,J)/CFROM does not over/underflow. TYPE specifies that
  A may be full, (block) upper triangular, (block) lower triangular,
  (block) upper Hessenberg, or banded.

</PRE>
<A name="Specification"><B><FONT SIZE="+1">Specification</FONT></B></A>
<PRE>
      SUBROUTINE MB01QD( TYPE, M, N, KL, KU, CFROM, CTO, NBL, NROWS, A,
     $                   LDA, INFO )
C     .. Scalar Arguments ..
      CHARACTER          TYPE
      INTEGER            INFO, KL, KU, LDA, M, N, NBL
      DOUBLE PRECISION   CFROM, CTO
C     .. Array Arguments ..
      INTEGER            NROWS ( * )
      DOUBLE PRECISION   A( LDA, * )

</PRE>
<A name="Arguments"><B><FONT SIZE="+1">Arguments</FONT></B></A>
<P>

<B>Mode Parameters</B>
<PRE>
  TYPE    CHARACTER*1
          TYPE indices the storage type of the input matrix.
          = 'G':  A is a full matrix.
          = 'L':  A is a (block) lower triangular matrix.
          = 'U':  A is a (block) upper triangular matrix.
          = 'H':  A is a (block) upper Hessenberg matrix.
          = 'B':  A is a symmetric band matrix with lower bandwidth
                  KL and upper bandwidth KU and with the only the
                  lower half stored.
          = 'Q':  A is a symmetric band matrix with lower bandwidth
                  KL and upper bandwidth KU and with the only the
                  upper half stored.
          = 'Z':  A is a band matrix with lower bandwidth KL and
                  upper bandwidth KU.

</PRE>
<B>Input/Output Parameters</B>
<PRE>
  M       (input) INTEGER
          The number of rows of the matrix A.  M &gt;= 0.

  N       (input) INTEGER
          The number of columns of the matrix A.  N &gt;= 0.

  KL      (input) INTEGER
          The lower bandwidth of A.  Referenced only if TYPE = 'B',
          'Q' or 'Z'.

  KU      (input) INTEGER
          The upper bandwidth of A.  Referenced only if TYPE = 'B',
          'Q' or 'Z'.

  CFROM   (input) DOUBLE PRECISION
  CTO     (input) DOUBLE PRECISION
          The matrix A is multiplied by CTO/CFROM. A(I,J) is
          computed without over/underflow if the final result
          CTO*A(I,J)/CFROM can be represented without over/
          underflow.  CFROM must be nonzero.

  NBL     (input) INTEGER
          The number of diagonal blocks of the matrix A, if it has a
          block structure.  To specify that matrix A has no block
          structure, set NBL = 0.  NBL &gt;= 0.

  NROWS   (input) INTEGER array, dimension max(1,NBL)
          NROWS(i) contains the number of rows and columns of the
          i-th diagonal block of matrix A.  The sum of the values
          NROWS(i),  for  i = 1: NBL,  should be equal to min(M,N).
          The array  NROWS  is not referenced if NBL = 0.

  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
          The matrix to be multiplied by CTO/CFROM.  See TYPE for
          the storage type.

  LDA     (input) INTEGER
          The leading dimension of the array A.  LDA &gt;= max(1,M).

</PRE>
<B>Error Indicator</B>
<PRE>
  INFO    INTEGER
          Not used in this implementation.

</PRE>
<A name="Method"><B><FONT SIZE="+1">Method</FONT></B></A>
<PRE>
  Matrix A is multiplied by the real scalar CTO/CFROM, taking into
  account the specified storage mode of the matrix.
  MB01QD is a version of the LAPACK routine DLASCL, modified for
  dealing with block triangular, or block Hessenberg matrices.
  For efficiency, no tests of the input scalar parameters are
  performed.

</PRE>

<A name="Comments"><B><FONT SIZE="+1">Further Comments</FONT></B></A>
<PRE>
  None
</PRE>

<A name="Example"><B><FONT SIZE="+1">Example</FONT></B></A>
<P>
<B>Program Text</B>
<PRE>
  None
</PRE>
<B>Program Data</B>
<PRE>
  None
</PRE>
<B>Program Results</B>
<PRE>
  None
</PRE>

<HR>
<p>
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