Frequently Asked Questions:

  Q:  Has the SLATEC source been modified?
  A:  No.  These are the version 4.1 SLATEC routines exactly as
      provided by netlib.

  Q:  Why take only the double precision routines?
  A:  Many of the function evaluations in SLATEC are carried out
      by truncated Taylor series expansions.  The number of terms
      retained in these expansions dictate that the single precision
      routines are really only accurate for 32 bit floating point
      arithmetic.  The double precision routines are good for 64 bits.
      On Cray systems, R8slatec is compiled to map double precision to
      Cray single precision.  Thus the library can be used in a REAL*8
      code with portability between Cray and conventional 32 bit 
      workstation environments.  A goal of the NTCC Modules Library
      is to encourage portable fortran programming practices.  There
      is no hope for the portability of single precision codes, hence
      the choice to include only the double precision (really, 64 bit)
      SLATEC routines.

  Q:  Why take only the C category subset of SLATEC?
  A:  SLATEC includes a version of BLAS and other routines which are
      better distributed by other means.  In the case of BLAS in
      particular, users should seek system provided routines that are
      optimized to the local machine architecture.

  Q:  I have a code which makes single precision SLATEC calls.  How
      can I make use of this library?
  A:  This would only be practical in the context of converting your
      code to REAL*8 precision.  The NTCC Modules Library includes a set
      of "portability tools" to facilitate this conversion.  One of 
      the tools, inside the "ftoken" module, is a tool called "fgtok".
      The R8slatec modules contains a file "slatec_r8.table" which 
      contains the mapping of SLATEC names from single to double
      precision, in a format understood by fgtok.  So,

         fgtok    -s slatec_r8.table

      will convert all single precision SLATEC special function calls.
      The conversion of fortran code to REAL*8 precision is highly 
      desirable, because the result is code which runs identically on
      Cray and on workstation environments.
  Q:  where can I find documentation for these routines.
  A:  the source code comments give very precise definitions of the
      interfaces of individual routines.  For more general information
      point your browser at "".