/// @ref gtx_matrix_query

namespace glm
{
	template<typename T, qualifier Q>
	GLM_FUNC_QUALIFIER bool isNull(mat<2, 2, T, Q> const& m, T const& epsilon)
	{
		bool result = true;
		for(length_t i = 0; result && i < m.length() ; ++i)
			result = isNull(m[i], epsilon);
		return result;
	}

	template<typename T, qualifier Q>
	GLM_FUNC_QUALIFIER bool isNull(mat<3, 3, T, Q> const& m, T const& epsilon)
	{
		bool result = true;
		for(length_t i = 0; result && i < m.length() ; ++i)
			result = isNull(m[i], epsilon);
		return result;
	}

	template<typename T, qualifier Q>
	GLM_FUNC_QUALIFIER bool isNull(mat<4, 4, T, Q> const& m, T const& epsilon)
	{
		bool result = true;
		for(length_t i = 0; result && i < m.length() ; ++i)
			result = isNull(m[i], epsilon);
		return result;
	}

	template<length_t C, length_t R, typename T, qualifier Q>
	GLM_FUNC_QUALIFIER bool isIdentity(mat<C, R, T, Q> const& m, T const& epsilon)
	{
		bool result = true;
		for(length_t i = 0; result && i < m.length(); ++i)
		{
			for(length_t j = 0; result && j < glm::min(i, m[0].length()); ++j)
				result = abs(m[i][j]) <= epsilon;
			if(result && i < m[0].length())
				result = abs(m[i][i] - 1) <= epsilon;
			for(length_t j = i + 1; result && j < m[0].length(); ++j)
				result = abs(m[i][j]) <= epsilon;
		}
		return result;
	}

	template<typename T, qualifier Q>
	GLM_FUNC_QUALIFIER bool isNormalized(mat<2, 2, T, Q> const& m, T const& epsilon)
	{
		bool result(true);
		for(length_t i = 0; result && i < m.length(); ++i)
			result = isNormalized(m[i], epsilon);
		for(length_t i = 0; result && i < m.length(); ++i)
		{
			typename mat<2, 2, T, Q>::col_type v;
			for(length_t j = 0; j < m.length(); ++j)
				v[j] = m[j][i];
			result = isNormalized(v, epsilon);
		}
		return result;
	}

	template<typename T, qualifier Q>
	GLM_FUNC_QUALIFIER bool isNormalized(mat<3, 3, T, Q> const& m, T const& epsilon)
	{
		bool result(true);
		for(length_t i = 0; result && i < m.length(); ++i)
			result = isNormalized(m[i], epsilon);
		for(length_t i = 0; result && i < m.length(); ++i)
		{
			typename mat<3, 3, T, Q>::col_type v;
			for(length_t j = 0; j < m.length(); ++j)
				v[j] = m[j][i];
			result = isNormalized(v, epsilon);
		}
		return result;
	}

	template<typename T, qualifier Q>
	GLM_FUNC_QUALIFIER bool isNormalized(mat<4, 4, T, Q> const& m, T const& epsilon)
	{
		bool result(true);
		for(length_t i = 0; result && i < m.length(); ++i)
			result = isNormalized(m[i], epsilon);
		for(length_t i = 0; result && i < m.length(); ++i)
		{
			typename mat<4, 4, T, Q>::col_type v;
			for(length_t j = 0; j < m.length(); ++j)
				v[j] = m[j][i];
			result = isNormalized(v, epsilon);
		}
		return result;
	}

	template<length_t C, length_t R, typename T, qualifier Q>
	GLM_FUNC_QUALIFIER bool isOrthogonal(mat<C, R, T, Q> const& m, T const& epsilon)
	{
		bool result = true;
		for(length_t i(0); result && i < m.length(); ++i)
		{
			result = isNormalized(m[i], epsilon);
			for(length_t j(i + 1); result && j < m.length(); ++j)
				result = abs(dot(m[i], m[j])) <= epsilon;
		}

		if(result)
		{
			mat<C, R, T, Q> tmp = transpose(m);
			for(length_t i(0); result && i < m.length(); ++i)
			{
				result = isNormalized(tmp[i], epsilon);
				for(length_t j(i + 1); result && j < m.length(); ++j)
					result = abs(dot(tmp[i], tmp[j])) <= epsilon;
			}
		}
		return result;
	}
}//namespace glm