Re: compact notation for NonCommutativeMultiply that supports cut and paste

*To*: mathgroup at smc.vnet.net*Subject*: [mg127657] Re: compact notation for NonCommutativeMultiply that supports cut and paste*From*: "djmpark" <djmpark at comcast.net>*Date*: Sun, 12 Aug 2012 01:49:37 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net*References*: <8525141.75636.1344674234471.JavaMail.root@m06>

I think you are saying that you don't like the x**y**z space taking infix operator of NonComutativeMultiple and want something more compact because of long multiplication sequences. I think it is a bit confusing to have no infix separator (Is every argument guaranteed to be a single character symbol?). The following uses a Vertical line and negative spaces to make a pretty compact form. Unprotect[NonCommutativeMultiply]; NonCommutativeMultiply /: MakeBoxes[NonCommutativeMultiply[x__ /; Length[{x}] > 1], form : (StandardForm | TraditionalForm)] := Module[{displayFunc, interpretationFunc, work1, work2, work3, n = Length[{x}], f}, work1 = Riffle[Table[Slot[i], {i, n}], RowBox[{"\[NegativeThinSpace]", "\[NegativeMediumSpace]", "|", "\[NegativeMediumSpace]", "\[NegativeThinSpace]"}]]; work2 = RowBox@work1; displayFunc = (Evaluate@work2) &; work3 = Riffle[Table[Slot[i], {i, n}], ","]; interpretationFunc = f[(RowBox[{"NonCommutativeMultiply", "[", Sequence @@ work3, "]"}])] /. f -> Function; TemplateBox[MakeBoxes[#, form] & /@ {x}, "NonCommutativeMultiply", DisplayFunction -> displayFunc, InterpretationFunction -> interpretationFunc] ] NonCommutativeMultiply[a, b, T, dd, F] % // FullForm % // InputForm TemplateBox is an undocumented, but rather nifty construction, that I got from WRI support some time ago. It can be copied and pasted. You can edit the variables but not other parts of the expression. Someone from WRI might give a neater formulation of this. David Park djmpark at comcast.net http://home.comcast.net/~djmpark/index.html From: tobiashagge at gmail.com [mailto:tobiashagge at gmail.com] Hello, I am doing some group theory computations that have output of the form := NonCommutativeMultiply[very-long-sequence-of-letters] I want the StandardForm output to display as a string of symbols without spaces, just like the output of Times. I want to be able to copy and paste that output into an input line and have it be correctly interpreted. Finally, I want "a b" to evaluate as Times[a,b]. I decided to define the null character as an operator, piecing together bits of code from the internet. Unprotect[NonCommutativeMultiply]; InfixNotation[ParsedBoxWrapper["\[Null]"], NonCommutativeMultiply]; NonCommutativeMultiply /: MakeBoxes[NonCommutativeMultiply[x__], StandardForm] := RowBox[Riffle[(MakeBoxes[#, StandardForm]) & /@ {x}, ConstantArray[ "\[InvisibleSpace]\[Null]\[InvisibleSpace]", Length[{x}] - 1]]]; I'm having two issues: 1) The special characters are not visible in the notebook, which makes the code a bit hard to read. 2) Letters appear spaced apart in the output. If you copy and paste the output, the spacing disappears (so pushing the letters together in the output using negative space will make copy/paste awkward). Using AlignmentMarker instead of Null fixes the spacing issue. However, for reasons I do not understand, the InfixNotation command does not work in this case. Any help or helpful advice is appreciated. Best, Tobias