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slartgp.f(3)                        LAPACK                        slartgp.f(3)


NAME

       slartgp.f -


SYNOPSIS

   Functions/Subroutines
       subroutine slartgp (F, G, CS, SN, R)
           SLARTGP generates a plane rotation so that the diagonal is
           nonnegative.

Function/Subroutine Documentation
   subroutine slartgp (realF, realG, realCS, realSN, realR)
       SLARTGP generates a plane rotation so that the diagonal is nonnegative.

       Purpose:

            SLARTGP generates a plane rotation so that

               [  CS  SN  ]  .  [ F ]  =  [ R ]   where CS**2 + SN**2 = 1.
               [ -SN  CS  ]     [ G ]     [ 0 ]

            This is a slower, more accurate version of the Level 1 BLAS routine SROTG,
            with the following other differences:
               F and G are unchanged on return.
               If G=0, then CS=(+/-)1 and SN=0.
               If F=0 and (G .ne. 0), then CS=0 and SN=(+/-)1.

            The sign is chosen so that R >= 0.

       Parameters:
           F

                     F is REAL
                     The first component of vector to be rotated.

           G

                     G is REAL
                     The second component of vector to be rotated.

           CS

                     CS is REAL
                     The cosine of the rotation.

           SN

                     SN is REAL
                     The sine of the rotation.

           R

                     R is REAL
                     The nonzero component of the rotated vector.

             This version has a few statements commented out for thread safety
             (machine parameters are computed on each entry). 10 feb 03, SJH.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           September 2012

       Definition at line 96 of file slartgp.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2                   Sat Nov 16 2013                   slartgp.f(3)

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