Re: plot solution derivative
- To: mathgroup at smc.vnet.net
- Subject: [mg108268] Re: plot solution derivative
- From: "Kevin J. McCann" <Kevin.McCann at umbc.edu>
- Date: Fri, 12 Mar 2010 07:10:03 -0500 (EST)
- References: <op.u9c2oxvv422244@toshiba> <hnakjb$5rr$1@smc.vnet.net>
Try this: tZeroDeriv = t /. Solve[deriv2func == 0, t] (* Pick out the real values*) zd = Extract[tZeroDeriv, Position[tZeroDeriv, _?(Im[#] == 0 &)]] (* Now plot and use Epilog to put in the vertical lines *) Plot[{deriv2func}, {t, First[First[date]], First[Last[date]]}, Frame -> True, GridLines -> Automatic, PlotRange -> {-0.1, 0.5}, Epilog -> {Red, (Line[{{#, -0.1}, {#, 0.5}}] &) /@ zd}] Kevin Beata Warcho? wrote: > Dear Math Group, > > I need your help in this problem: > > I have date and function for example: > date= {{39814.`, 876.34`}, {39817.`, 859.91`}, {39818.`, > 864.55`}, {39819.`, 840.95`}, {39820.`, 853.95`}, {39821.`, > *** snip *** > 1017.2`}}; > func = Fit[date, Table[t^i, {i, 0, 49}], t]; > deriv2func = \!\( > \*SubscriptBox[\(\[PartialD]\), \(t, t\)]func\); > and plot: > Plot[{deriv2func}, {t, First[First[date]], First[Last[date]]}, > Frame -> True, GridLines -> Automatic] > and I would like to plot additionally in this graph vertically lines, i= n > points which are solution of equation > deriv2fun == 0, > > Maybe I need something like this > Reduce[deriv2func == 0 && 38000 < t < 41000, t, Reals], but how sho= uld I > plot this? > > Beata > >