Richard Maine wrote:
> Martin Jørgensen <megaf...@hotmail.com> wrote:

>> integer, parameter, dimension(4) :: odd(1,3,5,7)
>> integer, parameter, dimension(4) :: even(2,4,6,8)

> This is almost valid, but doesn't mean what you think. The (1,3,5,7) is
> not an array of values. It is the dimensions, overriding the
> dimension(4). And you don't specify a value at all, which is what makes
> it invalid. What you want is more like

>   integer, parameter, dimension(4) :: odd = [1,3,5,7]

> where I'm using the f2003 square bracket array constructor syntax. If
> your compiler doesn't accept that, substitute (/1,3,5,7/), but do note
> that you cannot use just (1,3,5,7).

>> even_index = [2 4 6 8 10]
>> odd_index = [1 3 5 7 9]

> That is fine if you declared even_index and odd_index appropriately. You
> do, however, need declarations.

>> somearray(even_index) = somearray(even_index) * 2.0
>> somearray(odd_index) = somearray(odd_index) * 2.0

> This is ok, once you defined even_index and odd_index appropriately. But
> there is a lot simpler way. Just do

>   somearray(2::2) = somearray(2::2) * 2.0  !-- For the even ones
>   somearray(1::2) = somearray(1::2) * 2.0  !-- For the odd ones

>> Is it possible? I get compiler error when I try it...

> It helps to say what the compiler error is... and what code it goes
> with, as you show multiple alternatives above.