formatting - Format string for output dependent on a variable

Question

I would like to have a Fortran write statement formatted to depend on some variable. For example, I could write:

write(*,'(3f15.3,3f9.2)') x,y,z,(var(i),i=1,nvari)

where nvari = 3. But, what if, in some cases, I actually have 4 variables (i.e. nvari = 4). I would like to write something like this:

write(*,'(3f15.3,nvari(f9.2))') x,y,z,(var(i),i=1,nvari)

Now, nvari can be anything and the output will work as I like. How can I make something like this work?

Answer 1

If you are using Intel fortran, it has a proprietary extension for this -- you can include an existing variable in angle brackets to act as a specifier:

  write(*,'(3f15.3,<nvari>f9.2)') x,y,z,(var(i),i=1,nvari)