[Splines] Remove is_radial

Author: blegouix

include/ddc/kernels/splines/bsplines_non_uniform.hpp

@@ -51,11 +51,6 @@ class NonUniformBSplines : detail::NonUniformBSplinesBase
         return Tag::PERIODIC;
     }
 
-    static constexpr bool is_radial() noexcept
-    {
-        return false;
-    }
-
     static constexpr bool is_uniform() noexcept
     {
         return false;

include/ddc/kernels/splines/bsplines_uniform.hpp

@@ -50,11 +50,6 @@ class UniformBSplines : detail::UniformBSplinesBase
         return Tag::PERIODIC;
     }
 
-    static constexpr bool is_radial() noexcept
-    {
-        return false;
-    }
-
     static constexpr bool is_uniform() noexcept
     {
         return true;

include/ddc/kernels/splines/spline_builder.hpp

@@ -51,7 +51,6 @@ class SplineBuilder
              && (BcXmax == ddc::BoundCond::PERIODIC))
             || (!BSplines::is_periodic() && (BcXmin != ddc::BoundCond::PERIODIC)
                 && (BcXmax != ddc::BoundCond::PERIODIC)));
-    static_assert(!BSplines::is_radial());
 
 private:
     using tag_type = typename InterpolationMesh::continuous_dimension_type;