HP FORTRAN 77 Elements [ HP FORTRAN 77 Quick Reference Guide ]
HP FORTRAN 77 Quick Reference Guide
Chapter 1 HP FORTRAN 77 Elements
HP FORTRAN 77 Elements
The HP FORTRAN 77 Character Set
Each language element is written using the letters A through Z, the
digits 0 through 9, and the following special characters:
Blank ( Left parenthesis
= Equals ) Right parenthesis
+ Plus , Comma
- Minus . Decimal point
* Asterisk ' Single quotation mark
(apostrophe)
/ Slash " (Double) quotation mark
! Exclamation point $ Dollar sign
_ Underscore (break) : Colon
Special Symbols
The special symbols are groups of characters that define specific
operators and values. The special symbols are:
** Exponentiation
.TRUE. Logical true
.FALSE. Logical false
.NOT. Logical negation
.AND. Logical AND
.OR. Logical OR
.EQV. Logical equivalence
.NEQV. Logical non equivalence (exclusive or)
.XOR. Same as .NEQV
.EQ. Equal
.NE. Not equal
.LT. Less than
.LE. Less than or equal
.GT. Greater than
.GE. Greater than or equal
Truth Table for Logical Operators
Table 1-1. Truth Table for Logical Operators
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| | | | | | | |
| a | b | .NOT.a | a.AND.b | a.OR.b | a.NEQV.b | a.EQV.b |
| | | | | | a.XOR.b | |
| | | | | | | |
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| | | | | | | |
| True | True | False | True | True | False | True |
| | | | | | | |
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| | | | | | | |
| True | False | False | False | True | True | False |
| | | | | | | |
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| | | | | | | |
| False | True | True | False | True | True | False |
| | | | | | | |
-------------------------------------------------------------------------------------------------------
| | | | | | | |
| False | False | True | False | False | False | True |
| | | | | | | |
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Keywords
Keywords are predefined FORTRAN entities that identify or appear in a
statement or compiler option. The keywords of FORTRAN are:
ASSIGN DO EXTERNAL NONE SUBROUTINE
BACKSPACE DOUBLE COMPLEX FORMAT OPEN SYSTEM INTRINSIC
BLOCK DATA DOUBLE PRECISION FUNCTION PARAMETER THEN
CALL ELSE GOTO PAUSE TO
CHARACTER ELSE IF IF PRINT WHILE
CLOSE ENCODE IMPLICIT PROGRAM WRITE
COMMON END INCLUDE READ
COMPLEX ENDDO INQUIRE REAL
CONTINUE ENDIF INTEGER RETURN
DATA ENDFILE INTRINSIC REWIND
DECODE ENTRY LOGICAL SAVE
DIMENSION EQUIVALENCE NAMELIST STOP
Data Types
The HP FORTRAN 77 data types are shown below; storage is measured in
8-bit bytes.
Table 1-2. Data Types
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| | | |
| TYPE | RANGE | STORAGE |
| | | |
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| | | |
| integer | -2147483648 to +2147483647 | 4 bytes |
| | | |
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| | | |
| short integer | -32768 to +32767 | 2 bytes |
| | | |
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| | | |
| real | system dependent* | 4 bytes |
| | | |
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| | | |
| double precision | system dependent* | 8 bytes |
| | | |
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| | | |
| complex | same as real | 8 bytes |
| | | |
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| | | |
| double complex | same as double precision | 16 bytes |
| | | |
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| | | |
| logical | .TRUE. or .FALSE. | 4 bytes |
| | | |
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| | | |
| short logical | .TRUE. or .FALSE. | 2 bytes |
| | | |
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| | | |
| character | entire 8-bit ASCII character | 1 byte (for each character) |
| | set | |
| | | |
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