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HELP FOR: grdisplay
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CALLING SEQUENCE: grdisplay ( objectSeq ):

PARAMETERS:       objectSeq - GRTensorII object name or sequence of object
                              names

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SYNOPSIS:

- Displays the components of the GRTensorII object(s) specified.

- The object must have been previously calculated (using grcalc()) in
  order to be displayed.

- Only non-zero elements of tensors are displayed. The value of
  a scalar is always displayed.

- Symmetries of the tensor objects are used to reduce the number
  of components displayed. For example, the metric tensor is symmetric
  so only the non-zero components in the upper diagonal are displayed.

- If multiple metrics have been loaded then the objects from the
  non-default metric can be displayed by putting the metric name
  in square braces. See the example below.

- Objects whose size (measured in MapleV words) exceeds the value of the
  global variable grOptionDisplaySize will have their length displayed
  instead of their value. This limit can be changed by assigning the option
  variable a new value. See ?groptions.

- For 1- and 2-index objects, the output is in the form of a matrix
  unless the size of one of the tensor components exceeds the value of the
  global grOptionTermSize variable. Otherwise regular individual component
  display is used. See ?groptions.

- The use of coordinate names vs coordinate numbers in the output is
  controlled by the global grOptionCoordNames variable. See ?groptions.

- To reduce the size of tensor components, simplification routines 
  can be applied using gralter() and grmap().

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EXAMPLES:

> qload ( schw ):
> grcalc ( R(dn,dn) ):
> grdisplay( R(dn,dn) ):
                       Covariant Ricci

                R(dn,dn) =  All components are zero

> qload ( bondi ):
> grdisplay ( R(dn,dn) ):

R(dn,dn) has not been calculated.

> grdisplay( R[schw](dn,dn) ):

                       Covariant Ricci

                R(dn,dn) =  All components are zero

> grdisplay ( g[schw](dn,dn) ):

                            Covariant metric tensor

                              For the schw metric.

                                             1
                             g r r     = ---------
                                         1 - 2 m/r

                                                 2
                             g theta theta  =   r

                                          2           2
                             g phi phi = r  sin(theta)

                               g t t = - 1 + 2 m/r

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SEE ALSO: grcalc, gralter, grmap, grt_objects, grt_commands, groptions.
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