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S Yuan wrote: > For the following Common block: > > common A(10,3,3) > ... > common B(10,3),C1(15),C2(15) > > how can I replace it with F90 features? > > What I can do is > > real,target :: A(10,3,3) > real,pointer:: B(:,:),C1(:),C2(:) > B => A(:,:,1) > > but then > C1 => ? The answer to your first question depends, in part, on things you haven't told us. First, I assume that the two common statements you've shown us are in different program units. If that were not the case, using a pointer to make B be an alias for part of A would be entirely off track. The critical issue is whether the program ever puts a value into B, C1, or C2 and expects to retrieve it from A or vice versa. The fact that C1 and C2 correspond to rather odd pieces of A suggests that it is quite likely that the program _does not_, and that this was just a trick to reduce the total amount of storage allocated. In that case, you don't have to do much of anything other than declare A, B, C1, and C2 as ordinary arrays in their respective program units. Unlike most FORTRAN 77 implementations, most Fortran 90 implementations naturally reuse the storage for local variables that do not have the SAVE attribute. [Additionally, this trick only saved 60 words of storage, an amount too small to be worth worrying about on any modern system.] If the program _does_ put values in one variable and take them out of another, you pointer approach could be made to work: call HELPER(C1,A(1,1,2),15) ! HELPER does the pointer assignment call HELPER(C2,A(6,2,2),15) where HELPER is defined something like subroutine HELPER(POINTER,TARGET,LENGTH) real,pointer:: POINTER(:) real,target :: TARGET(LENGTH) POINTER => TARGET end subroutine HELPER However, the unnecessary use of pointers tends to adversely affect code optimization, so I would be more inclined to just put the statements real :: A(10,3,3),B(10,3),C1(15),C2(15) equivalence (A,B),(A(1,1,2),C1),(A(6,2,2),C2)) into a module. Equivalences also have an effect on optimization, but it is much less severe. Since it is a bit of a pain to figure out that C2(1) corresponds to A(6,2,2), I might actually do the equivalences in terms of an underlying one-dimensional array: real :: SMAP(90),A(10,3,3),B(10,3),C1(15),C2(15) equivalence (SMAP(1),A,B),(SMAP(31),C1),(SMAP(46),C2) -Kurt