FPUT_IEEE(L)




   NAME
     FPUT_IEEE


   SYNOPSIS
     CALL FPUT_IEEE (A,	dim, fn, u, offs, ier)


   ACCESS
     Cray C90 and Cray J90


   DESCRIPTION
     FPUT_IEEE,	part of	the PFIO_IEEE library,	converts an array of CRI
     floating point data to the	T3D IEEE format, opens an unblocked data file
     and writes	values from the	array to the indicated file.

     There are two basic modes of operation.  Shared files may be written to
     concurrently by multiple processors.  Individual files may	also be
     opened and	written	into concurrently by multiple processors.

     The FPUT_IEEE routine is asynchronous.  Explicit synchronization, where
     required, must be provided	by the user.

     A	  (IN)	 REAL array of size dim.

		 On each processor that	calls FGET_IEEE,
		 array A is written to file fn,	unit u,
		 at word offset	offs*dim.

		 See the examples below.

     dim  (IN)	 INTEGER.  Dimension of	A.

     fn	  (IN)	 CHARACTER*(*) array.  Name of global
		 output	file.

     u	  (IN)	 INTEGER.  Unit	number associated with
		 file fn.

     offs (IN)	 INTEGER.  Record number for direct access
		 file fn.

     ier  (OUT)	 INTEGER.  Return code from an OPEN statement
		 on file fn with status='unknown'.


   RESTRICTIONS
     Direct-access file	errors may be observed when the	same unit is used by
     FPUT_IEEE to write	files and then by FGET_IEEE to read them.  For these
     cases, use	of distinct unit numbers is recommended.



									    1






   FPUT_IEEE(L)



   ERROR CHECKING
     The FPUT_IEEE routine uses	the ASSIGN statement to	modify the buffering
     of	file I/O.  Conversion from CRI format to T3D IEEE floating point is
     accomplished by calling CRAY2IEG.	Non-zero error codes are printed to
     stdout.  See the Cray I/O User's Manual and the Scientific	Library
     Reference Manual for further detail.


   EXAMPLE
     The following example associates unit 10 with direct access file 'test'
     and opens it with record length 1024.  The	file is	entered	at record
     number offset and the first 1024 words of array A are written at this
     position.

	  call FPUT_IEEE (A, 1024, 'test', 10, offset, ier)

     This example associates unit my_unit with the private file	my_file.
     Both the unit id and filename in this case	might depend on	the process
     number.  Each process executing this FPUT call opens the indicated
     direct access file	with record length 4096, enters	it at the first
     record, and writes	the record data	into array B.

	  call FGET_IEEE (B, 4096, my_file, my_unit, 1,	ier)

     Upon completion of	the write within FPUT, the indicated file is closed
     and control is returned to	the caller.  Synchronization may be required
     between calls to FPUT/FGET	when a common file name	or unit	id is
     involved.


   SEE ALSO
     FGET_IEEE(L), FPUT(L), FGET(L), ASSIGN(1),	CRAY2IEG(3F)


   REFERENCES
     O'Neal, D.	C., and	Reddy, N. R., "Solving Symmetric Eigenvalue Problems
     on	Distributed Memory Machines,"  1994 Fall Proceedings, Cray User
     Group, Tours, France, p. 76-96.


   MORE	INFORMATION
     More information on this topic is maintained on PSC's World Wide Web
     (WWW) server.  For	details	on accessing our WWW server, execute "man
     wwwinfo" on any PSC system.

     If	you are	already	familiar with WWW, and would like to go	directly to
     additional	information for	PFIO_IEEE, the URL is

      http://pscinfo.psc.edu/general/software/packages/pfio_ieee/pfio_ieee.html






   2