Entering Material Data
For most material data, you have the option to choose between From material and User defined. The preferred way of supplying the material data, is through the Materials node. If you are using data from the Material Library, this is the only option, but also when supplying your own data this will improve clarity of model.
Constitutive matrices, such as the elasticity matrix for an anisotropic material, are in many cases per definition symmetric. Only the upper diagonal of the matrix given as input is used for forming the matrix used, so you need not enter the lower diagonal part.