| Introduction |
| |
| Differences between Fortran 77 and Fortran 90/95 |
| |
| Differences |
| 1) Fortran 90 has more intrinsic functions than
Fortran 77, and it adds intrinsic subroutines. |
| |
| The CF90 compiler accepts the following
intrinsic functions, which are included in the Fortran 90 standard: |
| |
| ADJUSTL |
ADJUSTR |
ALL |
ALLOCATED |
ANY |
| ASSOCIATED |
BIT_SIZE |
COUNT |
CSHIFT |
DIGITS |
| DOT_PRODUCT |
EOSHIFT |
EPSILON |
EXPONENT |
FRACTION |
| HUGE |
KIND |
lLBOUND |
LEN_TRIM |
MATMUL |
| MAXEXPONENT |
MAXLOC |
MAXVAL |
MERGE |
MINEXPONENT |
| MINLOC |
MINVAL |
NEAREST |
PACK |
PACK CISION |
|
| |
| 2) All Fortran 77 commands remain same but some of them like GO
TO and COMMON are made obsolete. |
| Fortran 90 |
| Important features of Fortran 90 are as follows: |
· Dynamic Memory Allocation
· Array processing Features
· Structured Data Types
· Modules and Pointers |
| |
| 3) The Fortran 77 end the program with END statement but Fortran
90 ends their program with
END PROGRAM name of program.
|
| 4) In Fortran 77 a statement can start from column 7 and extend
to 72 but in Fortran 90 a statement can
start from column 1 and extend to column 132. |
|
5) Differences between Relational Operators can be seen in the
table: |
| Operation |
Fortran
77 form |
Fortran
90 form |
| Less
than |
.
LT . |
< |
| Less
than or equal to |
.
LE . |
<= |
| Equal
to |
.
EQ . |
=
= |
| Greater
than |
.
GT . |
> |
| Greater
than or equal to |
.
GE . |
>= |
| Not
equal to |
.
NE . |
!= |
|
| |
| |
|
| |
| |
