Question

I am intending to make a constant Vector

const  madness::Vector<double,3> kvec(0.0, 0.0, 1.0);

By calling the following code

template <typename T>
Vector<T,3> vec(T x, T y, T z) {
   Vector<T,3> r; r[0] = x; r[1] = y; r[2] = z;
   return r;
}

Unfortunately, I get an error which seems to say

extra.cc:216: error: no matching function for call to ‘madness::Vector<double, 3ul>::Vector(double, double, double)’
note: candidates are: madness::Vector<T, N>::Vector(const madness::Vector<T, N>&) [with T = double, long unsigned int N = 3ul]
note:                 madness::Vector<T, N>::Vector() [with T = double, long unsigned int N = 3ul]

I can’t help but notice the 3ul in the error message. Why does the compiler think my innocent little three is an unsigned long?

Thanks in advance,
Nick

Answer 1

is your Vector class template perhaps:

template<typename T, size_t N> class Vector ...

And is your size_t perhaps an unsigned long?

Also, I suspect you really meant:

const  madness::Vector<double,3> kvec = vec(0.0, 0.0, 1.0);