Re: Interpolation of a tabulated function

*To*: mathgroup at smc.vnet.net*Subject*: [mg115589] Re: Interpolation of a tabulated function*From*: Bill Rowe <readnews at sbcglobal.net>*Date*: Sat, 15 Jan 2011 04:47:35 -0500 (EST)

On 1/14/11 at 6:16 AM, irexxy at gmail.com (girl17) wrote: >So, I have a list for tabulated function like that: >{{x1,y1},{x2,y2},...,{xn,yn}}, where x(i+1)-xi are not equal for all >i. I want to get an interpolated function for that array and to use >this function in this way: intFucn[x], where x1<=x<=xn. I tried to >use ListInterpolation[], but it works only for 1D lists, i.e. in >case if x(i+1)-xi are equal for all i. Is there any solution for >this problem? Use Interpolation. Note, the problem you are describing above is a 1D problem. For this type of problem, the number of dimensions is the number of coordinates needed to express the result. For each input value x you have a single number y as the result, making this a 1D problem. ListInterpolation is not restricted to 1D lists. The following taken from the documentation page for ListInterpolation works just fine f = ListInterpolation[ Table[Sin[x y], {x, 0, 1, .25}, {y, 0, 2, .25}], {{0, 1}, {0, 2}}] Show[{Plot3D[f[x, y], {x, 0, 1}, {y, 0, 2}], Graphics3D[{Red, PointSize[0.03], Table[Point[{x, y, Sin[x y]}], {x, 0, 1, .25}, {y, 0, 2, .25}]}]}]