Re: Re: datelistplot - log axis for values

*To*: mathgroup at smc.vnet.net*Subject*: [mg82891] Re: [mg82825] Re: [mg82806] datelistplot - log axis for values*From*: "Thomas Dowling" <thomasgdowling at gmail.com>*Date*: Fri, 2 Nov 2007 03:34:15 -0500 (EST)*References*: <200710311116.GAA22567@smc.vnet.net>

Does this work? Tom Dowling On 11/1/07, Carl Woll <carlw at wolfram.com> wrote: > > sdw wrote: > > >Hi - > > > >Does anyone have a clever way to make datelistplot act like loglistplot > and create nice log Y axis vs. dates? > > > >this is not the same as just logging the y variable before plotting - I > want the Y axis to show the actual values on a log scale, not the log values > on a linear scale > > > >thanks, > > > >Steven > > > > > > > > > One way is to use the internal function used by LogPlot and friends. > First, make Mathematica load the .mx file necessary for LogPlot > functionality: > > In[1]:= LogPlot > > Out[1]= LogPlot > > Next, let's make some data: > > data = CountryData["US", {"GDP", All}]; > > We need to scale the data: > > scaledata = data; > scaledata[[All, -1]] = Log[scaledata[[All, -1]]]; > > Now, we use the internal function Graphics`LogPlotDump`LogScale (this is > why we executed In[1], as this function would be undefined if we hadn't): > > ticks = Graphics`LogPlotDump`LogScale[Min[scaledata[[All, -1]]], > Max[scaledata[[All, -1]]]]; > > Finally, you are ready to make the DateListPlot: > > DateListPlot[scaledata, FrameTicks -> {Automatic, ticks, True, None}] > > <plot snipped> > > Carl Woll > Wolfram Research > >