When the curvilinear coordinate system is generated the transformation and therefore the set of mapping functions , is known. Then we are able to derive expressions for the differential operators in the curvilinear coordinates using the elements of the Jacobian of the transformation .
Partial derivatives with respect to cartesian coordinates are related to partial derivatives with respect to curvilinear coordinates by the chain rule which may be written in either of two ways. To start, we consider a continuously differentiable scalar-valued function . Then, we may use (3.3-44) or, equivalently, (3.3-45) to relate the cartesian and curvilinear derivatives of the function .
We easily identify in the first case the contravariant base vectors and , whereas in the second case the covariant base vectors and .