On 2 Mar 2004 at 02:26 PST, Joerg Stiller wrote:
>
> Thank you Mike. I should have mentioned, of course, that I am specifically
> interested in the case of a single real (or double precision) array, say
> a(m,n).
The assign(1) layer on all Cray systems provides a host of conversion methods
under the -N option. Here is an excerpt from the Cray X1 man page for assign:
-N numcon Specifies foreign numeric conversion. Used by Fortran I/O.
Fortran unformatted I/O converts numeric data from this
assumed numeric format on input, and converts it to this
numeric format on output.
If this option is used and the -C option is not used,
appropriate character defaults are used.
Each value for numcon selects a particular type of foreign
data conversion. Each option has a mapping that associates
each of the native data types with a corresponding foreign
data type and length in bits. Appropriate data conversion is
done on unformatted input and output operations.
The following table lists the valid values for numcon on
different hardware platforms. Note that in these tables, vax
is an alias for vms.
Table 3. Cray X1 systems (IEEE)
----------------------------------------------------------------
-N option -C default Meaning
----------------------------------------------------------------
none none No data conversion
default default No data conversion
cray ascii Cray ``classic'' floating-
point
ibm ebcdic IBM 360/370-style data
conversion
vms ascii VAX/VMS data conversion
ieee ascii Generic IEEE data (no data
conversion)
ieee_32 Generic 32-bit IEEE data. No
data conversion except for
items which are promoted via
-sdefault64 (or -sreal64 or
-sinteger64). They are
handled as if they had not
been promoted; that is,
default-sized variables are
read and written as if no -s
option is specified.
mips ascii SGI MIPS IEEE data
conversion (128-bit
floating-point is ``double
double'' format)
ieee_64 ascii Cray 64-bit IEEE data
conversion
ieee_le ascii Little endian 32-bit IEEE
data conversion
ultrix Alias for above
t3e ascii Cray 64-bit IEEE data
conversion; denormalized
numbers flushed to zero
t3d Alias for above
user ascii User-defined data conversion
site ascii Site-defined data conversion
ia ascii Intel architecture
----------------------------------------------------------------
--
Ted Stern Applications Group
Cray Inc. office: 206-701-2182
411 First Avenue South, Suite 600 cell: 206-383-1049
Seattle, WA 98104-2860 FAX: 206-701-2500
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(The Paleontological Society motto, equally apropos for debugging)
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