Load the package

The latest version of the package can always be downloaded from
    http://metric.iem.csic.es/Martin-Garcia/xAct/

This loads the package from the default directory, for example $Home/.Mathematica/Applications/xAct/ for a single-user installation under Linux (see the installation notes for other possibilities),

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<<xAct`xTensor`

Memory, in bytes, used by both Mathematica and xAct`, and then xAct` alone:

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Note the structure of the ContextPath. There are six contexts: xAct`xTensor`, xAct`xPerm`, xAct`xCore` and xAct`ExpressionManipulation` contain the respective reserved words. System` contains Mathematica's reserved words. The current context Global` will contain your definitions and right now it is empty.

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We turn off the annoying spell messages (since version 0.9.3 this is done by default when reading xCore`):

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Additional technical notes:
There are several global variables that can be useful at loading time:
- If the variable xAct`xTensor`$ReadingVerbose is defined and has value True before loading the package, then several messages are printed while reading the package. This can be used to debug the input file in case there are errors at that point.
- The variables xAct`xCore`$Version, xAct`xPerm`$Version and xAct`xTensor`$Version contain the respective versions of the packages. The variable xAct`xTensor`$xPermExpectedVersion contains the oldest valid version of the package xPerm` which is fully compatible with the current version of xTensor`.
- The messages printed by xAct`xCore`Disclaimer[], xAct`xPerm`Disclaimer[] and xAct`xTensor`Disclaimer[] are identical.

Created by Mathematica  (May 16, 2008)