Plot function at specific points

*To*: mathgroup at smc.vnet.net*Subject*: [mg114094] Plot function at specific points*From*: István Zachar <zac at freemail.hu>*Date*: Tue, 23 Nov 2010 06:00:36 -0500 (EST)

Dear Group, is there a method to plot an InterpolatingFunction at specific pointr WITHIN Plot? I am of course aware that I can use ListPlot at any time, though for certain reasons I have to stick with Plot. The main reason is that I have a large amount of InterpolatingFunctions which I plot with Plot as default, though at request I have to plot the same InterpolatingFunctions at different resolutions. PlotPoints and MaxRecursion is no good here, since lower resolution has to use a certain set of x-values, defined prior to plotting. Obviously I want to use the same Plot setup for both high and low-resolution cases. Below is a toy modell of the problem: f = Interpolation[{{0, 1}, {1, 2}, {2, 3}, {3, 5}, {4, 8}, {5, 5}, {6, 2}, {7, 1}, {8, 1}, {9, 2}, {10, 4}}]; lowRes = Range[0, 10, 2]; Plot[f[x], {x, 0, 10}, PlotRange -> {{0, 10}, {0, 9}}] ListLinePlot[{#, f@#} & /@ lowRes, PlotRange -> {{0, 10}, {0, 9}}] Again, what I want is to have a specific Plot call instead of the ListLinePlot, but with same result as ListLinePlot. Note that values of 'lowRes' may not correspond the exact x- coordinates supplied to f. Is there a way to tell Plot explicitly the steps to use? Any idea? Istvan