I recommend having your class in a namespace with related functions. A big reason for this is argument-dependent lookup (ADL). When you call a non-member function that has a class type argument, the function name is looked up in the enclosing namespace of that class. So if you have, say:
namespace foo {
class bar { };
void baz(bar);
}
If you ever want to call baz, you won't need to explicitly give the namespace it is contained in, you can simply do:
foo::bar x;
baz(x);
Without qualifying baz, the compiler still found the function because it is within a namespace that encloses the type of its argument. In this way, C++ considers the contents of the enclosing namespace of a class to be part of the interface of that class. Implementing functions that are part of the interface of a class as non-member non-friend functions in this way, allowing ADL to find the function, increases encapsulation. If a function doesn't need access to the internals of a class, don't make it a member of that class - instead, put it in the same namespace as that class.
It's suspicious that your namespace has the same name as your class, however. Usually there will be more than one class within a namespace, and even if there weren't, the names would be different. The name of the namespace should describe its contents, not just the single class inside it.
