Symbol Tensor is Protected. Symbol TensorType is Protected. Symbol TensorName is Protected. is because you loaded TensoriaCalc more than once in the same kernel session. When writing the package, I had to Protect all the symbols used in the package, such as Tensor, Metric, etc. This means their definitions cannot be altered by an external user. I've no knowledge in mathematica (but I do in matlab), but I'd really appreciate if someone could mention what is/are the best and easy to learn mathematica package(s) for symbolic and numerical (both, really) computation of Riemannian geometry, specially Christoffel symbols, sectional curvature, and parallel transport along a given curve on M, given the topological type of the manifold M and. Oct 19,  · Christoffel symbol exercise: calculation in polar coordinates part II Christoffel Symbol or Connection coefficient Riemann curvature tensor and Ricci tensor for the 2-d surface of a sphere Metric tensor exercise: calculation for the surface of a sphere Geodesic equation and Christoffel symbols.