3 ms·
Early Fortran already had loops, but with labels: INTEGER A(4,4), C, R ... DO 10 WHILE ( C .NE. R ) A(C,R) = A(C,
by spacechild1 4y ago
Early Fortran already had loops, but with labels:
INTEGER A(4,4), C, R
...
DO 10 WHILE ( C .NE. R )
A(C,R) = A(C,R) + 1
C = C+1
10 CONTINUE
Note that Fortran has evolved significantly over time. This is how you would write the same in Fortran 77:
INTEGER A(4,4), C, R
...
C = 4
R = 1
DO WHILE ( C .GT. R )
A(C,R) = 1
C = C - 1
END DO
- bee_rider 4y agoThose are just regular loops, though, right? I’m looking for the posttest loop, sometimes known as the do…while or until loop. There seems to be a unfortunate inconsistency in the naming of this thing.
- spacechild1 4y agoAh, right, I misread your post. DO WHILE is indeed a "normal" while loop. There doesn't seem to be an equivalent to "do { ... } while", as found in most C-style languages. > There seems to be a unfortunate inconsistency in the naming of this thing. Well, Fortran is older than C, so you cannot really blame them :-)
- bee_rider 4y agoThe funny thing is, I mostly program in Fortran (thus the interest in this construct). It is nice for expressing “this iterative method must be run at least once.” Unfortunately at some point I absorbed the name that comes from the C-ism, haha.
- spacechild1 4y agoMay I ask what field you're working in? Physics?
- int_19h 4y agoA less ambiguous name for those is repeat/until, as seen in Pascal and its descendants - I don't recall any language that uses that syntax for anything other than a postcondition loop.