############################################################################# # # FILE readme.txt of the Canon package - Installation Instructions # # Language: Maple 6, 7, 8, 9. # # Description: Puts tensor expressions (or expressions with indexed objects) # into the canonical form with respect to index ordering. The # indexed objects can obey generic permutation symmetries and # can have dummy indices. # The tensor expression must be in the explicit index notation, # and the product must be commutative (this is easily extended # to anticommutative or non-commutative case - it was not done # because Maple does not have a robust non-commutative product). # The metric tensor associated to the dummy indices can be # symmetric (tensor calculus), antisymmetric (spinor calculus), # or can have no symmetry (affine tensor calculus). # We are using the name "tensor" meaning "indexed object" in # general. # # Developers: Leon R. U. Manssur and Renato Portugal # Laboratorio Nacional de Computacao Cientifica (LNCC) # # Web page: http://www.cbpf.br/~portugal/Canon.html # # Contact and bug report: Portugal@Lncc.Br # ############################################################################# # # COPYRIGHT NOTICE # # The Canon package has all rights reserved to the developers. The package # and documentation are provided as is, without guarantee of support or # maintenance. We are not liable for any damages resulting in any way from # Their use. # # Everyone is granted permission to copy, modify and redistribute the # package and documentation, provided that, (1) all copies contain this # notice in the main program file and in the documentation, (2) no charge # is made for this software or works derived from it. # ############################################################################# INSTALLATION INSTRUCTIONS The Canon package is distributed free of charge. The authors kindly ask that researchers who have used the package cite references describing it. To download the current version of the Canon package, please use the following address: http://www.cbpf.br/~portugal/Canon.html Installation instructions: 1. Download the file Canon.zip into your machine. It contains the following files: code (Canon.m), help file (maple.hdb), source code (Canon.mpl), test file (test.mpl), paper describing the package (Canon.pdf), this file (readme.txt). 2. Unzip the file Canon.zip (with unzip or pkzip). 3. Save the code and the help files in a directory. Let's say C:\Canon. 4. Start a Maple session. Issue the command: libname := `C:/Canon`, libname; or libname := `C:\\Canon`, libname; The next command is: with(Canon); The output is something like: [CanonDefine, CanonPrint, CanonUnPrint, Canonical, CanonicalOne] NOTE: In Windows one can use the forward slash ("/") or a double back slashes ("\\") in directory names. You can use the package now. For help try ?CanonDefine or ?Canon ... If anything goes wrong, give the command restart before trying again. The command with(Canon); means that Maple is going to read the file C:\Canon\Canon.m, if libname has been set up correctly. The command ?CanonDefine means that Maple is going to look for the definetensor help page within the file C:\Canon\maple.hdb . Example: > libname:= `C:/Canon`, libname: > with(Canon); [CanonDefine, CanonPrint, CanonUnPrint, Canonical, CanonicalOne] Try some help command: > ?Canon or > CanonPrint(T[a,-b]); a T b test: > read(`C:/Canon/test.mpl`); ---> if everything is ok, nothing will be printed Possible problems: If you have received the message: Error, (in with) undefined package , Canon after loading the package then there are two possibilities. Either Canon.m file is not in the directory C:\Canon or the variable libname has not been setup properly. In the first case you must redo the second step paying attention to the file paths. In the second case you should verify if the value of the variable libname is the correct one. Also verify if the name Canon is spelled correctly with capital letter. Restart the session and try again. If you have received the message: Could not find any help on ''topic'' then verify if the file maple.hdb is in the directory c:\Canon. If it is there then verify if the variable libname is the correct one. Maple can find the Canon help worksheets only by using the variable libname. Hint: One can avoid to setup every time the variable libname by putting this information in the maple initialization file (see ?maple and ?libname). For unix users: the initialization file is called .mapleinit and stays in the home directory. One should edit it and add the line: libname := `C:/Canon`, libname: