Re: Using Locators in Mathematica v6

*To*: mathgroup at smc.vnet.net*Subject*: [mg76472] Re: Using Locators in Mathematica v6*From*: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>*Date*: Wed, 23 May 2007 05:07:04 -0400 (EDT)*Organization*: Uni Leipzig*References*: <f2u4tq$jv5$1@smc.vnet.net>*Reply-to*: kuska at informatik.uni-leipzig.de

Hi, what is with data = Table[{x, 1 + 2*x + 0.5*Random[]}, {x, -2, 2, 0.2}]; Manipulate[ DynamicModule[{points, dfit, plt}, points = Append[data, pnt]; dfit = Fit[points, {1, x}, x]; Plot[dfit, {x, -2, 2}, Evaluated -> True , Epilog -> {Point /@ data}] ], {{pnt, {0, 0}}, Locator}] Regards Jens Coleman, Mark wrote: > Greetings, > > I've been exploring some of the new dynamic interface elements in Mathematica v6 > and I must say they are very impressive indeed. I've managed to set-up > some useful examples using Manipulate. Unfortunately the documentation > of > > One example I am working on involves the use of Locators. The example > itself seem straightforward but I cannot quite get the effect I am > looking for. I am hoping someone on MathGroup can point me in the right > direction. > > Briefly, I want to illustrate the effects that outlier points an have on > a line of best fit. For my example, I generate a small random set of > points (x(i), y(i)), where y(i) = a + b x(i) + randomerror(i), for > values a and b. I then calculate the line of best fit using Fit[ ]. I > next ListPlot[ ] the underlying set of points and overlay the resulting > line from Fit[ ]. So far very simple. > > In my dynamic example, I'd like to have a locator button appear on the > graph such that the (x,y) location of the locator becomes an additional > data point in the overall data set, and thereafter a new line of best > fit is calcuated and displayed. Thus as the user moves the locator, a > new best fit line is displayed. > > I'd appreciate any assistance other readers might offer. > > Thanks, > > -Mark