syntax - matrix manipulation SciLab -

i heard there way change matrix values without using loop. example:

a = [1 2; 3 4]

there suppose way can make values example less 4 , changed them other value, let's zero. this:

a(...<4...)=0

and answer should be:

 ans  =  0.    0.   0.    4.

anyone know syntax this?

you don't need use find this; can use indexing instead :

a(a>=4) = 0;

Stadnd