Using NDSolve and Finding a specific Value

*To*: mathgroup at smc.vnet.net*Subject*: [mg85354] Using NDSolve and Finding a specific Value*From*: Tara.Ann.Lorenz at gmail.com*Date*: Thu, 7 Feb 2008 04:44:28 -0500 (EST)

Hello. I am having an issue related to the NDSolve function (I am using Version 6). The following example illustrates the problem I am having: Input: sols = NDSolve[{i'[t] == (1/8.516011) (-i[t] + 0.596120754), i[1] == 0.219319}, i[t], {t, 1, 4}] Output: {{i[t]->InterpolatingFunction[{{1.,4.}},<>][t]}} I then would like to solve i[t] for t=3.8 According to the Mathematica website, I should be able to enter the following input to receive my answer: i[3.8]/.sols However, my output is simply i[3.8] and not a numerical value. What else can I try to get a numerical value from the interpolating function. I appreciate any feedback. Thank you