command line arguments in array in Java

command line arguments in array in Java

I am a very beginner in Java, I have a question regarding to use command
line arguments line in array, for example, I tried to type:
double []a=Double.parseDouble(args[0]);
however, it said" cannot convert double to double",I cannot figure out it,
as I can do
double a=Double.parseDouble(args[0]);
so what is wrong with using CL arguments input in array then?Thanks