HP OpenVMS Systems Documentation 
HP Fortran for OpenVMS

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Table 94 lists the specific functions that have no generic function associated with them.
Specific Function  Class  Value Returned 

DPROD (X, Y)  E  The higher precision product of two real arguments 
DREAL (A)  E  The corresponding doubleprecision value of the real part of a doublecomplex argument 
EOF (A)  I  .TRUE. or .FALSE. depending on whether a file is beyond the endoffile record 
MALLOC (I)  E  The starting address for the block of memory allocated 
MULT_HIGH (I, J)  E  The upper (leftmost) 64 bits of the 128bit unsigned result. 
NUMBER_OF_PROCESSORS
([DIM]) 
I  The total number of processors (peers) available to the program 
MY_PROCESSOR
( ) 
I  The identifying number of the calling process 
NWORKERS ( ) ^{1 }  I  The number of executing processes 
PROCESSORS_SHAPE ( )  I  The shape of an implementationdependent hardware processor array 
QREAL (A)  E  The corresponding REAL(16) value of the real part of a COMPLEX(16) argument 
RAN (I)  N  The next number from a sequence of pseudorandom numbers (uniformly distributed in the range 0 to 1) 
SECNDS (X)  E  The system time of day (or elapsed time) as a floatingpoint value in seconds 
SIZEOF (X)  I  The bytes of storage used by the argument 
EElemental
IInquiry
NNonelemental
Table 95 lists the intrinsic subroutines. All these subroutines are nonelemental except for MVBITS.
Subroutine  Value Returned or Result 

CPU_TIME (TIME)  The processor time in seconds 
DATE (BUF)  The ASCII representation of the current date (in ddmmmyy form) 
DATE_AND_TIME ([DATE] [,TIME]
[,ZONE] [,VALUES]) 
Date and time information from the realtime clock 
ERRSNS ([IO_ERR] [,SYS_ERR] [,STAT]
[,UNIT] [,COND]) 
Information about the most recently detected error condition 
EXIT ([STATUS])  Optionally returns image exit status; terminates the program, closes all files, and returns control to the operating system 
FREE (A)  Frees memory that is currently allocated 
IDATE (I, J, K)  Three integer values representing the current month, day, and year 
MVBITS (FROM, FROMPOS, LEN,
TO, TOPOS) ^{1} 
Copies a sequence of bits (bit field) from one location to another 
RANDOM_NUMBER (HARVEST)  A pseudorandom number taken from a sequence of pseudorandom numbers uniformly distributed within the range 0 <= x < 1 
RANDOM_SEED ([SIZE] [,PUT] [,GET])  Initializes or retrieves the pseudorandom number generator seed value 
RANDU (I1, I2, X)  A pseudorandom number as a singleprecision value (within the range 0.0 to 1.0) 
SYSTEM_CLOCK ([COUNT]
[,COUNT_RATE] [,COUNT_MAX]) 
Data from the processors realtime clock 
TIME (BUF)  The ASCII representation of the current time (in hh:mm:ss form) 
Integer data types are represented internally in binary twos complement notation. Bit positions in the binary representation are numbered from right (least significant bit) to left (most significant bit); the rightmost bit position is numbered 0.
The intrinsic functions IAND, IOR, IEOR, and NOT operate on all of the bits of their argument (or arguments). Bit 0 of the result comes from applying the specified logical operation to bit 0 of the argument. Bit 1 of the result comes from applying the specified logical operation to bit 1 of the argument, and so on for all of the bits of the result.
The functions ISHFT and ISHFTC shift binary patterns.
The functions IBSET, IBCLR, BTEST, and IBITS and the subroutine MVBITS operate on bit fields.
A bit field is a contiguous group of bits within a binary pattern. Bit fields are specified by a starting bit position and a length. A bit field must be entirely contained in its source operand.
For example, the integer 47 is represented by the following:
Binary pattern:  0...0101111 
Bit position:  n...6543210 
Where
n is the number of bit positions
in the numeric storage unit. 
You can refer to the bit field contained in bits 3 through 6 by specifying a starting position of 3 and a length of 4.
Negative integers are represented in twos complement notation. For example, the integer 47 is represented by the following:
Binary pattern:  1...1010001 
Bit position:  n...6543210 
Where n is the number of bit positions
in the numeric storage unit. 
The value of bit position n is as follows:
1 for a negative number
0 for a nonnegative number
All the highorder bits in the pattern from the last significant bit of the value up to bit n are the same as bit n.
IBITS and MVBITS operate on general bit fields. Both the starting position of a bit field and its length are arguments to these intrinsics. IBSET, IBCLR, and BTEST operate on 1bit fields. They do not require a length argument.
For IBSET, IBCLR, and BTEST, the bit position range is as follows:
For IBITS, the bit position can be any number. The length range is 0 to 63.
The following example demonstrates IBSET, IBCLR, and BTEST:
I = 4 J = IBSET (I,5) PRINT *, 'J = ',J K = IBCLR (J,2) PRINT *, 'K = ',K PRINT *, 'Bit 2 of K is ',BTEST(K,2) END 
The results are: J = 36, K = 32, and Bit 2 of K is F.
For optimum selection of performance and memory requirements, HP Fortran provides the following integer data types:
Data Type  Storage Required (in bytes) 

INTEGER(1)  1 
INTEGER(2)  2 
INTEGER(4)  4 
INTEGER(8)  8 
The bit manipulation functions each have a generic form that operates on all of these integer types and a specific form for each type.
When you specify the intrinsic functions that refer to bit positions or that shift binary patterns within a storage unit, be careful that you do not create a value that is outside the range of integers representable by the data type. If you shift by an amount greater than or equal to the size of the object you're shifting, the result is 0.
Consider the following:
INTEGER(2) I,J I = 1 J = 17 I = ISHFT(I,J) 
The variables I and J have INTEGER(2) type. Therefore, the generic function ISHFT maps to the specific function IISHFT, which returns an INTEGER(2) result. INTEGER(2) results must be in the range 32768 to 32767, but the value 1, shifted left 17 positions, yields the binary pattern 1 followed by 17 zeros, which represents the integer 131072. In this case, the result in I is 0.
The previous example would be valid if I was INTEGER(4), because ISHFT would then map to the specific function JISHFT, which returns an INTEGER(4) value.
If ISHFT is called with a constant first argument, the result will either be the default integer size or the smallest integer size that can contain the first argument, whichever is larger.
This section contains detailed information on all the generic and specific intrinsic procedures. These procedures are described in alphabetical order by generic name (if there is one). In headings, square brackets denote optional arguments; in text, these optional arguments are labeled "(opt)".
Description:  Computes an absolute value.  
Class:  Elemental function; Generic  
Arguments:  A must be of type integer, real, or complex.  
Results:  If A is an integer or real value, the value of the result is A; if A is a complex value (X, Y), the result is the real value SQRT (X**2 + Y**2). 
Specific Name  Argument Type  Result Type 

INTEGER(1)  INTEGER(1)  
IIABS  INTEGER(2)  INTEGER(2) 
IABS ^{1}  INTEGER(4)  INTEGER(4) 
KIABS  INTEGER(8)  INTEGER(8) 
ABS  REAL(4)  REAL(4) 
DABS  REAL(8)  REAL(8) 
QABS  REAL(16)  REAL(16) 
CABS ^{2}  COMPLEX(4)  REAL(4) 
CDABS ^{3 }  COMPLEX(8)  REAL(8) 
CQABS  COMPLEX(16)  REAL(16) 
Examples
ABS (7.4) has the value 7.4.
ABS ((6.0, 8.0)) has the value 10.0.
Description:  Returns the character in a specified position of the ASCII character set, even if the processor's default character set is different. It is the inverse of the IACHAR function. In HP Fortran, ACHAR is equivalent to the CHAR function.  
Class:  Elemental function; Generic  
Arguments:  I must be of type integer.  
Results: 
The result is of type character with length 1; it has the kind
parameter value of KIND (
'
A
'
).
If I has a value within the range 0 to 127, the result is the character in position I of the ASCII character set. ACHAR (IACHAR(C)) has the value C for any character C capable of representation in the processor. 
Examples
ACHAR (71) has the value ' G ' .
ACHAR (63) has the value ' ? ' .
Description:  Produces the arccosine of X.  
Class:  Elemental function; Generic  
Arguments:  X must be of type real. The X must be less than or equal to 1.  
Results:  The result type is the same as X and is expressed in radians. The value lies in the range 0 to Pi sign. 
Specific Name  Argument Type  Result Type 

ACOS  REAL(4)  REAL(4) 
DACOS  REAL(8)  REAL(8) 
QACOS  REAL(16)  REAL(16) 
Examples
ACOS (0.68032123) has the value .8225955.
Description:  Produces the arccosine of X.  
Class:  Elemental function; Generic  
Arguments:  X must be of type real and must be greater than or equal to zero. The X must be less than or equal to 1.  
Results:  The result type is the same as X and is expressed in degrees. 
Specific Name  Argument Type  Result Type 

ACOSD  REAL(4)  REAL(4) 
DACOSD  REAL(8)  REAL(8) 
QACOSD  REAL(16)  REAL(16) 
Examples
ACOSD (0.886579) has the value 27.55354.
Description:  Adjusts a character string to the left, removing leading blanks and inserting trailing blanks.  
Class:  Elemental function; Generic  
Arguments:  STRING must be of type character.  
Results: 
The result is of type character with the same length and kind parameter
as STRING.
The value of the result is the same as STRING, except that any leading blanks have been removed and inserted as trailing blanks. 
Examples
ADJUSTL ( ' SUMMERTIME ' ) has the value ' SUMMERTIME ' .
Description:  Adjusts a character string to the right, removing trailing blanks and inserting leading blanks.  
Class:  Elemental function; Generic  
Arguments:  STRING must be of type character.  
Results: 
The result is of type character with the same length and kind parameter
as STRING.
The value of the result is the same as STRING, except that any trailing blanks have been removed and inserted as leading blanks. 
Examples
ADJUSTR ( ' SUMMERTIME ' ) has the value ' SUMMERTIME ' .
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