Question In Regards To

[Lookingforhelponline]

Hello again. I made it back after writing a new code by myself, but I need help once again in executing a function. Pretty much I am trying to do something along the lines of:

D=x+y+z

DO x=1,20,5
DO y=1,20,5
DO z=1,20,5
ENDDO
ENDDO
ENDDO

MIN(Dall) [if Dall would be all of the values of D calculated]

Where all possible combinations of x,y,z are used from the ranges I provided and all possible values of D are calculated, so that I can have the smallest value as my output from that range of data. My issue is I don't know how to make that happen or actually break the code down further into something else entirely to get the same result.

Thanks in advance for your time and consideration.

 

[melmacianalf]

program min_xyz                                                                           
                                                                                          
  implicit none                                                                           
                                                                                          
  integer,parameter :: N = 1000                                                           
  integer           :: x, y, z, cnt, D, Dall(1:N)                                         
                                                                                          
  cnt = 0                                                                                 
                                                                                          
  do x = 1, 20, 5                                                                         
  do y = 1, 20, 5                                                                         
  do z = 1, 20, 5                                                                         
                                                                                          
    cnt = cnt + 1                                                                         
                                                                                          
    D = x + y + z                                                                         
    Dall(cnt) = D                                                                         
                                                                                          
  enddo                                                                                   
  enddo                                                                                   
  enddo                                                                                   
                                                                                          
  print *, minval(Dall(1:cnt))                                                                                                                                          
                                                                                          
end program min_xyz

Gordon Shumway

 

[gummibaer]

Or, a little less heavy on memory, if you just need the minimum value of D and not the complete matrix:

function min (x, y, z)
    implicit none
    integer :: x, y, z, DMin

    DMin = 2000000000    ! just a very big number 
    do x = 1, 20, 5
    do y = 1, 20, 5
    do z = 1, 20, 5
        DMin = min (DMin, x + y + z) 
    enddo
    enddo
    enddo

    Print *, DMin
end function

Where all possible combinations of x,y,z are used ... and all possible values of D are calculated

... but you do not do this when you select an increment of 5 in the loops (??)

Norbert


The optimist believes we live in the best of all possible worlds - the pessimist fears this might be true.

 

[ArkM]

What's a funny problem!
The answer is 3.
No need to twist these strange loops

Incidentally, there are only 64 elements in Dall array and max value of x+y+z is equal to 48...

 

[gummibaer]

Yes of course. I thought that this simple formula was just a placeholder for a more difficult thing.



The optimist believes we live in the best of all possible worlds - the pessimist fears this might be true.