166. Beware of a loop to huge(i), since huge(i)+1 is out of range.

topic: Loops

Note

This tip is a draft1.

To loop from 1 to a large number, with the loop terminated by an EXIT, write

do i=1,huge(i)-1 ! code if (cond) exit end do

It is invalid for the upper bound to be huge(i), since i is set to huge(i)+1 upon exit, which is out of range.

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To loop from 1 to a large number, with the loop terminated by an EXIT, write

do i=1,huge(i)-1
! code
if (cond) exit
end do

It is invalid for the upper bound to be huge(i), since i is set to huge(i)+1 upon exit, which is out of range.pic.twitter.com/bv6j43P7d8

— FortranTip (@fortrantip) March 26, 2022

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1

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