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[tamara]

Hi All,

sorry I'm a bit new and inexperienced at programming in fortran. I have seen in the documentation that there is a random number generator incorporated with this compiler but I'm unable to come up with the correct way of calling this function from a programme I'm writing.

I was using

random = FUNCTION RANDOM@()

Where random is a declared real variable. Do I have to put something else to incorporate a library of functions at the beginning of the code?

Any suggestions?

Thanks
Tamara

[aebolzan]

Hello Tamara,

you should put something like...

subroutine my_sub
real*8 :: random,number
.......
number=random()
........
end subroutine my_sub

I wouldn't use random = random() as it could be rather confusing to use the name of a function as the name of one of my variables

Best regards,

Agustin

[Wilfried Linder]

To make the numbers a bit more random it is a good idea to initialise the generator with "call date_time_seed@()" before using random().

Regards, Wilfried

[tamara]

Thanks a lot for all the prompt answers - this is great and makes it easy.

However when I write what I think is the code aebolzan suggested I get the following error message when I try to compile the model:
'RANDOM is a routine name and cannot be used in this context'

Maybe I should add that the call to the random function is occuring in a loop statement

Thanks a lot
Tamara

[aebolzan]

I have just run this code and works fine:

program seeds
implicit none
real*8 random
real*8, dimension(:), allocatable ::seed
integer i
allocate (seed(100))
do i=1,100
seed(i) = random()*100.0
end do
print*,seed
end program seeds

I do not know how is your code....

Best regards,

Agustin

[tamara]

Thanks a lot - yes, that fixes the problem. I made a mistake when updating my code - I changed the variable name from 'random' to 'number' for the random number generator, but then did not change it later on in the programme. Sorry about the confusion.

Tamara