Silicon Graphics IRIS Workstation, User Manual

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86 IRIS WORKSTATION GUIDE
Version 1.0
Appendix D:
NOTE: It is tempting to use the PARAMETER statement
in FORTRAN to define constants for passing to the IRIS
Graphics Library. The user is forewarned that any
constants defined in a FORTRAN PARAMETER statement
are of type integer*4 . Specifically declaring these
constants to be of another type has no effect!
This set of problems changes if the $INT2 option to the FORTRAN compiler is
used. Refer to this option in the FORTRAN Reference manual for more
information.
D.5 FORTRAN 77 Revision Notes
In order to ease the task of porting FORTRAN 66 programs to FORTRAN 77,
Hollerith is now supported in the following contexts.
• Hollerith in DATA Statement - Values may now be expressed in
Hollerith notation ( nHxxxx ). Each Hollerith value initializes a single
data item. If the number of bytes required to fill the data item
exceeds the number of characters in the Hollerith data value, the
lengths are matched by padding the Hollerith value with blanks on
the right. If the Hollerith value is longer that the required number of
bytes, trailing bytes of the value are discarded. If non-character data
items are initialized using Hollerith notation, the $CHAREQU option
must be set.
• Hollerith in SUBROUTINE and FUNCTION calls - Actual arguments
may be expressed in Hollerith for user subroutine and function calls.
The address of a “read only” temporary that is initialized to an array
of characters as specified in the actual argument is passed to the
subprogram. Hollerith actual parameters are considered numeric or
logical, corresponding to formal parameters typed INTEGER , REAL ,
DOUBLE PRECISION , COMPLEX , or LOGICAL (any length, array
or non-array). Formal parameters that are of a CHARACTER type
should not be used with actual parameters expressed in Hollerith.
The $CHAREQU option must be set in order to use Hollerith in
actual argument lists.
• Hollerith in Assignment Statements - Assignment statements in
which the expression on the right hand side is a Hollerith value are
accepted. If the type of the left hand side is CHARACTER , the Hollerith
notation is considered the same as a quoted character string. In all
other cases, the $CHAREQU option must be set and assignment uses
the same conventions as data initialization (as described above).
• Using arrays as FORMAT specifiers - The system accepts an array
name as a format specifier. Thus, the following example