FW: make 1. x 10^-10 read simpl

*To*: mathgroup at smc.vnet.net*Subject*: [mg8885] FW: [mg8479] make 1. x 10^-10 read simpl*From*: Ersek_Ted%PAX1A at mr.nawcad.navy.mil*Date*: Tue, 30 Sep 1997 20:16:54 -0400*Sender*: owner-wri-mathgroup at wolfram.com

An obvious improvement on my earlier code is shown below. Sorry about the excess e-mail. Rob Peterson wrote: | | Seems like I am always losing graph space because the vertical axis is | labeled like "1. x 10^-10" (except the ^ isn't there). I can't seem to | find a way to make it take up half the space by showing simply | "10^-10". | I have been working with Rob on his problem. An example of a graphics Rob is talking about can be made using the following commands. In[1]:= h = 6.63*^-34; k = 1.38*^-23; c = 3.0*^8; c1 = 8*Pi*h*c; c2 = h*c/k; (* BlackBodyDistr Black Body distr vs T and lambda *) rho[lambda_, T_] := c1/(lambda^5*(Exp[c2/lambda/T] - 1)); <<Graphics`Graphics` In[2]:= LogLogPlot[rho[lambda/10^6, 300], {lambda, 0.5, 100}, PlotRange -> All ]; Out[2]= (* Graphics not shown. *) The resulting graphic has TickMarks on the vertical axis labeled 1. x 10^-4, 1. x 10^-10, 1. x 10^-16, etc. Most would rather not have the "1. x" displayed. I modified the standard package to produce better looking results (in my opinion). To do this I changed the definition of the LogTicks command in the Graphics.m package. The change I made is shown below. Please let me know If you think the code should not be changed, or if there is a better way to get the desired results. Once Graphics.m is modified as shown below, the commands above will produce a graphics with TickMarks labeled as 10^-4, 10^-10, 10^-16, etc. Question: What is the purpose of NumberForm[x] in the original code ? Ted Ersek _______________________________________ (* The original definition was: *) LogTicks[x_] := {Log[10., x],NumberForm[x]} (* My new definition is: *) LogTicks[x_]:= Module[{xx=MantissaExponent[N[x]], y=Rationalize[x]}, {Log[10. , x], Which[ x==0.01, 0.01, x==0.1, 0.1, IntegerQ[y]&&(y<1000), y, Part[xx, 1]==1.0, Superscript[10, Part[xx, 2]], Part[xx, 1]==0.1, Superscript[10, Part[xx, 2]- 1], True, x ] } ] ________________________________________ Notes: For some reason this didn't work if avoided use of N[x], and used xx=Mantissaexponent[x]. Also the use of Rationalize may not be necessary. I would need a deeper understanding of the package to resolve these questions. Under Windows 95 the Mma install program put the Graphics.m package in the following folder: C/ProgramFiles/WolframResearch/Mathematica/3.0/AddOns/StandardPackages/Graph ics