arrays with 2 indices

[consideration]

hi,

in fortran 77, what does the second indice mean when
an array "x(2,5)" is defined (in this case ->5<-)?

can anyone explain me this code :

q(a,b) = q(a,b) + q(a,c)

Why a second indice and for what ?

THANKS in Advance

 

[xwb]

In C++

x(2,5)  means x[2][5] or x[3][6] if you want to start from 1 and ignore the 0 index.

q(a,b) = q(a,b) + q(a,c) means q[a][b] += q[a][c]

It depends entirely on the program as to what the second index is used for. Probably some row column thing in a matrix.