Re: Proper way to return a string

Ron Shepard wrote:
In article <2006122715420316807-gsande@worldnetattnet>,
Gordon Sande <g.sande@xxxxxxxxxxxxxxxx> wrote:

Probably because for a character function you need to declare a
fixed size but it can vary if you use a subroutine.

Assuming that you use Fortran character variables for "strings". ;-)

Perhaps I misunderstand, but I think you have the same flexibility
with functions and subroutines. Since f77, both allow the result to
be declared as assumed length (i.e. (*), or in f90, (len=*)).

$.02 -Ron Shepard

As I understand it, a character(*) function returns a character
variable whose length is fixed by its caller. In the example below the
first program attempts to return a result of indeterminate length and
compilation fails. The second program does return a value which is then
truncated.

C:\g77>type foo1.f
character(*) zz

print *,'|',zz(),'|'
end

character(*) function zz()
zz='hello, world'
end

C:\g77>g77 foo1.f
foo1.f: In program `MAIN__':
foo1.f:1:
character(*) zz
1
foo1.f:3: (continued):
print *,'|',zz(),'|'
2
Invalid declaration of or reference to symbol `zz' at (2) [initially
seen at (1)
]

C:\g77>type foo2.f
character*10 zz

print *,'|',zz(),'|'
end

character(*) function zz()
zz='hello, world'
end

C:\g77>g77 foo2.f

C:\g77>a
|hello, wor|

C:\g77>

[I hope this rectifies my previous lack of understanding of this
subject. :-)]

e-mail: epc8 at juno dot com

.

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