A question about notation

[playmobil]

Hi guys

I am trying to understand a code from a book (I write few lines).

DO
f(1, = Fcn(x, y)
DO i=2, s
w = y + h*MATMUL(a(i, 1:i-1), f(1:i-1, )
f(i, = Fcn(x + c(i)*k, w)
END DO
END DO

It is clear for me the meaning of a(i, 1:i-1) but i did not find anything for f(1, , that is, when you have only :

Thanks in advance

 

[xwb]

The syntax is basically

array([start]:[end][:step=1],...)

where the items in [] are optional. So if f has been declared as f(-10:10,-9:9) it means f(1,-9:9)

You can do some pretty complicated stuff with this notation that you can't in any other language. For instance, you could assign all the odd members of an array to all the even elements of another array. It is basically an implied loop

integer::evens(20), odds(19)
...
evens(2::2) = odds(1::2)

 

[playmobil]

Thank you very much xwb =)