Re: CirclePlus precedence and bigoplus
- To: mathgroup at smc.vnet.net
- Subject: [mg36252] Re: CirclePlus precedence and bigoplus
- From: "Carl K. Woll" <carlw at u.washington.edu>
- Date: Wed, 28 Aug 2002 04:16:13 -0400 (EDT)
- Organization: University of Washington
- References: <ak4dvm$6e$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Lucas, One way to change the precedence of CirclePlus is to change the file UnicodeCharacters.tr. On my machine the file is located under ../4.1/SystemFiles/FrontEnd/TextResources Open up the file, search for CirclePlus, change the precedence from 450 to 420, and then save. Of course, it would be wise to make a backup copy of the file before you make any changes. Also, 420 is low enough to get the behavior you desire, but you may want to experiment with other precedences. Then, start mathematica and you will get the behavior you want. Carl Woll Physics Dept U of Washington "Lucas" <lscharen at d.umn.edu> wrote in message news:ak4dvm$6e$1 at smc.vnet.net... > Hello, > > I'm attempting to implement an abstract mathematica package in > mathematica that utilized the \[CirclePlus] operator in an unusual > way. Specifically, the \[CirclePlus] has a precidence lower than + > and introduces barriers in the computation. So, an expression such as > > a + b \[CirclePlus] c + d --> (a+b) \[CirclePlus] (c+d) > > The mathematica ouput of > > a + d + (b \[CirclePlus] c) is incorrect. I've tried playing with the > PrecedenceForm[] function, but that does not seem able to produce the > desired effect. > > Also, I would like to introduce a notation like > > N > \[BigCirclePlus] x[[i]] --> x[[1]] \[CirclePlus] x[[2]] \[CirclePlus] > .... > i=0 > > analagous to summation, but mathematica does not appear to offer the > CirclePlus in a large format. to relate this to the case above, x[1] > = (a + b) and > x[2] = (c + d), so each indexed element is a subexpression. > > Finally, I would like to be able to set up the CirclePlus operator > such that the following algebraic relations hold: > > > \Sum \BigCirclePlus E = \BigCirclePlus \Sum E > i j ij j i ij > > d d > -- \BigCirclePlus E = \BigCirclePlus -- E > dx j j j dx j > > > Thanks in advance for any help on the above. > > -Lucas Scharenbroich > -MLS Group / JPL >