Re: how do I display "Power[z,-1]" in an exponetial form?

*To*: mathgroup at smc.vnet.net*Subject*: [mg50794] Re: how do I display "Power[z,-1]" in an exponetial form?*From*: ab_def at prontomail.com (Maxim)*Date*: Tue, 21 Sep 2004 03:49:21 -0400 (EDT)*References*: <ci8mqm$bt3$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

dumstuck at gmx.ch (dumstuck at gmx.ch) wrote in message news:<ci8mqm$bt3$1 at smc.vnet.net>... > In the field of DSP engineering we like keeping the expression "1/z" > in the form of "z minus one", namly in a exponential form. Both the "z > minus one" and "1/z" has the same "FullForm", namely "Power[z,-1]". > But they both get displayed in a fractional form. how could I change > that way of diplaying "Power[z,-1]"? You can use MakeBoxes: MakeBoxes[k_. * x_ ^ n_, form_] := Module[ {kbox, xbox, nbox, powbox}, kbox = MakeBoxes[k, form]; xbox = MakeBoxes[x, form]; nbox = MakeBoxes[n, form]; If[Head @ xbox =!= String, xbox = RowBox[{"(", xbox, ")"}] ]; powbox = SuperscriptBox[xbox, nbox]; Switch[kbox, "1", powbox, RowBox[{"-", "1"}], RowBox[{"-", powbox}], _, RowBox[{kbox, " ", powbox}] ]] Evaluate -1/(a+Sqrt[b])-1/a^2 in the front end to see how the output will be formatted. It will work with StandardForm and TraditionalForm. There is no need for a 'reverse' MakeExpression definition, because the output can be correctly interpreted by Mathematica. FormatValues[MakeBoxes]={} will clear this definition. Maxim Rytin m.r at inbox.ru