Representation groups

Fiber Bundle HDF5 - Representation Structure (Representation group)

A Representation is a group of datasets which describes information of a set of elements relative to a given reference object. Such reference objects can be chart objects or other Topology objects. Additionally, each Representation subgroup contains an entry "Reference" which is a symbolic link to the actual HDF5 reference object.

Another reserved name is "Positions", which is a datasets containing "coordinate locations" for the given set. The term "coordinate locations" is meant somewhat more abstract if the base elements are note points in physical space. The "Positions" dataset in general refers to the essential information relating the base elements to the elements of the Reference object.

Examples for the "Positions" dataset:

• {x,y,z} coordinates of vertices in cartesian space
• {theta,phi} coordinates of vertices on a sphere
• {i,j,k} indices of the points which construct a triangle

Representation in cartesian coordinates:

Standard Cartesian Chart 3D
     |
     |===>   Positions  (Dataset of type CartesianChart3D::Point)
     |
     |==>    "density"      (float) 
     |
     |==>    "temperature"  (float) 
     |
     |==>    "velocity"   (Dataset of type CartesianChart3D::Vector)
     |
   [...]

Extensions and Restrictions

• "Reference" is a reserved name for the symbolic link to the referer object
• "Positions" is a reserved name for the positional component
• All datasets in a Representations group and below must share their dataspace, ie. be of the same size.