Indexed Objects

  This chapter is concerned with the basic data structure (the ``indexed object'') used in REDTEN and how it is created and accessed. The first part of the chapter describes the basic concept of the indexed object, its properties and how it is used with an index. The second part uses the Robertson-Walker metric as an example to illustrate the user interaction with the system.

• The Indexed Object
• Using mkobj()
  • name
  • indextype
  • Symmetries
    • Combining Symmetries
    • Constraints
  • implicit value
  • itype
  • Other properties
  • mkobj() Examples
• The Index
  • Differentiation
  • Shift Operations
  • Symmetrization
• The Robertson-Walker Metric
  • coords()
  • Entering Components
  • Accessing and Displaying Components