Portability Functions: Return double-precision random numbers in the range 0.0 through 1.0.
USE IFPORT
result = DRAND (iflag)
result = DRANDM (iflag)
iflag |
(Input) INTEGER(4). Controls the way the random number is selected. |
The result type is REAL(8). Return values are:
Value of iflag |
Selection process |
|---|---|
1 |
The generator is restarted and the first random value is selected. |
0 |
The next random number in the sequence is selected. |
Otherwise |
The generator is reseeded using iflag, then restarted, and the first random value is selected. |
There is no difference between DRAND and DRANDM. Both functions are included to insure portability of existing code that references one or both of them.
CONSOLE STANDARD GRAPHICS QUICKWIN GRAPHICS WINDOWS DLL LIB
USE IFPORT
REAL(8) num
INTEGER(4) f
f=1
CALL print_rand
f=0
CALL print_rand
f=22
CALL print_rand
CONTAINS
SUBROUTINE print_rand
num = drand(f)
print *, 'f= ',f,':',num
END SUBROUTINE
END