int x = 9; System.out.println( Math.sqrt( x ) );
3.0
Even though sqrt() expects a double
for an argument, here we gave it an int.
This is OK.
The compiler knows what sqrt() expects
and automatically inserts code to convert the argument to
the correct type.
When sqrt() is called it has the double precision
floating point argument that it expects.
Often programmers use a type cast to show explicitly where the type conversion takes place:
int x = 9; System.out.println( Math.sqrt( (double)x ) );
In the above code, the type case is not required, but it is used to clearly show what is intended. Sometimes a type cast is required.
What does the following fragment write?
int x = 1; int y = 9; System.out.println( Math.sqrt( x/y ) );
Warning: this is a trick question!