RE: Show[] applied to a Plot[] and a ListPlot[] ??
- To: mathgroup at smc.vnet.net
- Subject: [mg41041] RE: [mg41023] Show[] applied to a Plot[] and a ListPlot[] ??
- From: "Wolf, Hartmut" <Hartmut.Wolf at t-systems.com>
- Date: Wed, 30 Apr 2003 04:20:42 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
>-----Original Message----- >From: 1.156 [mailto:rob at piovere.com] To: mathgroup at smc.vnet.net >Sent: Tuesday, April 29, 2003 11:24 AM >To: mathgroup at smc.vnet.net >Subject: [mg41041] [mg41023] Show[] applied to a Plot[] and a ListPlot[] ?? > > >First I start with a few measured data points: > >data = {{0,260.}, {.25,218.},{.5,200.}, {.75,212.}, {1.,240.}}; > >(* I do some curve fitting/regression and I come up with a >polynomial and I'd like to see how the curve compares with the data *) > >a0 = 260.; a1 = -188.; a2 = -2.667; a3 = 384.; a4 = -213.333.; > >f[x_]= a0+ a1 x+ a2 x^2+ a3 x^3 +a4 x^4; > >(* So I plot each of them, both look good to me. a plots the >best fit curve and b plots the data points with nice big red >dots. I got the b code from some kind soul on this ng I >think. Both plots are over a domain from 0 to 1 *) > >a = Plot[f[x], {x, 0, 1}]; >b=ListPlot[data,Epilog\[Rule]{RGBColor[1,0,0],PointSize[0.025], >Point/@data}] > >(* now that I see that both plots work, I do my usual and Show >them together *) > >Show[{a,b}] > >But woe is me: I can see some of the b points as small black >dots (not RED!), and several I can't see at all next to the >plain black plot of a. This seems to work fine if both a and b >are standard Plot[] functions but here I'm mixing Plot[] and ListPlot[] >-- I'm definitely teasing the devil. > >Can someone give me a hint how to make Mathematica Show[] reveal the >nice big red dots >from a ListPlot in b while also displaying the Plot[] curve? > >Rob > Well, Rob, Show[b, a] ...will do. Why? Epilog is part of the Options, and in combined Show the options from the first Graphics are used (in addition to others specified explicitly). What you saw, were the minute small black dots from b. In fact, you put too much into b, no problems would have arisen with better b: bb = ListPlot[data, PlotStyle -> {RGBColor[1, 0, 0], PointSize[0.025]}] Show[a, bb] Using Epilog is more senseful with Plot[f[x], {x, 0, 1}, Epilog -> {RGBColor[1, 0, 0], PointSize[0.025], Point /@ data}] -- Hartmut Wolf