From: Viktor Toth <vttoth@us...>  20050325 11:57:11

Update of /cvsroot/maxima/maxima/doc/info In directory sc8prcvs1.sourceforge.net:/tmp/cvsserv15374 Modified Files: Itensor.texi Log Message: Restoring a previously omitted paragraph from old documentation files. Index: Itensor.texi =================================================================== RCS file: /cvsroot/maxima/maxima/doc/info/Itensor.texi,v retrieving revision 1.17 retrieving revision 1.18 diff u d r1.17 r1.18  Itensor.texi 23 Jan 2005 13:25:19 0000 1.17 +++ Itensor.texi 25 Mar 2005 11:57:02 0000 1.18 @@ 31,18 +31,26 @@ should keep in mind the following characteristics of the two implementations: i) The representation of tensors and tensor operations explicitly in +The representation of tensors and tensor operations explicitly in terms of their components makes CTENSOR easy to use. Specification of the metric and the computation of the induced tensors and invariants is straightforward. +is straightforward. Although all of MAXIMA's powerful simplification +capacity is at hand, a complex metric with intricate functional and +coordinate dependencies can easily lead to expressions whose size is +excessive and whose structure is hidden. In addition, many calculations +involve intermediate expressions which swell causing programs to +terminate before completion. Through experience, a user can avoid avoid +many of these difficulties. ii) Although all of MAXIMA's powerful simplification capacity is at hand, a complex metric with intricate functional and coordinate dependencies can easily lead to expressions whose size is excessive and whose structure is hidden. In addition, many calculations involve intermediate expressions which swell causing programs to terminate before completion. Through experience, a user can avoid avoid many of these difficulties. +Because of the special way in which tensors and tensor operations +are represented in terms of symbolic operations on their indices, +expressions which in the component representation would be +unmanageable can sometimes be greatly simplified by using the special +routines for symmetrical objects in ITENSOR. In this way the structure +of a large expression may be more transparent. On the other hand, because +of the the special indicial representation in ITENSOR, in some cases the +user may find difficulty with the specification of the metric, function +definition, and the evaluation of differentiated "indexed" objects. @subsection New Tensor Notation 