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 A subroutine naming  convention is  employed in  which each  subroutine
 name  is  a  coded  specification  of  the  computation  done  by  that
 subroutine.  All names consist of five  letter in the form TXXYY.   The
 first letter,  T, indicates  the matrix  data type.   Standard  FORTRAN
 allows the use of three such types:

        S       REAL
        D       DOUBLE PRECISION
        C       COMPLEX

 In addition,  some FORTRAN  systems (alas,  NOT the  DEC-20!)  allow  a
 double precision complex type:

        Z       COMPLEX*16

 The next  two letters,  XX, indicate  the  form of  the matrix  or  its

        CH      Cholesky decomposition
        GB      General band
        GE      General
        GT      General tridiagonal
        HI      Hermitian indefinite
        HP      Hermitian indefinite packed
        PB      Positive definite band
        PO      Positive definite
        PP      Positive definite packed
        PT      Positive definite tridiagonal
        QR      Orthogonal-triangular decomposition
        SI      Symmetric indefinite
        SP      Symmetric indefinite packed
        SV      Singular value decomposition
        TR      Triangular

 The  final  two  letters,  YY,  indicate  the  computation  done  by  a
 particular subroutine:

        CO      Factor and estimate condition
        DC      Decompose
        DD      Downdate
        DI      Determinant and/or inverse and/or inertia
        EX      Exchange
        FA      Factor
        SL      Solve
        UD      Update

 The following chart shows all the LINPACK subroutine.  The initial S in
 the names may  be replaced  by D, C,  or Z,  and the initial  C in  the
 complex-only names may be replaced by a Z.

                CO      FA      SL      DI
        SGE     *       *       *       *
        SGB     *       *       *       *
        SPO     *       *       *       *
        SPP     *       *       *       *
        SPB     *       *       *       *
        SSI     *       *       *       *
        SSP     *       *       *       *
        CHI     *       *       *       *
        CHP     *       *       *       *
        STR     *               *       *
        SGT                     *
        SPT                     *

                DC      SL      UD      DD      EX
        SCH     *               *       *       *
        SQR     *       *
        SSV     *