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Re: Getting the value of the independent var from the dep.var using NDSolve

• To: mathgroup at smc.vnet.net
• Subject: [mg63891] Re: Getting the value of the independent var from the dep.var using NDSolve
• From: "Borut Levart" <BoLe79 at gmail.com>
• Date: Sat, 21 Jan 2006 01:50:38 -0500 (EST)
• References: <dptd4r$be$1@smc.vnet.net><dq2rgc$n0o$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

Commenting on the last comment, I would like to say:
- what a nice differential-equation platform NDSolve is,
- and that the above example fails to find the peaks of Sin[x]:

NDSolve[
    {
      y'[x] == Cos[x],
      y[0] == 0}, y, {x, 0, 20},
    Method -> {
        "EventLocator",
        "Event" -> y[x] - 1,
        "EventAction" :> Sow[x]
        }
    ] // Reap

Why is that?
I guess the solver steps over the event, which in turn is not noticed.
But could any algorithm not miss that?

• Follow-Ups:
  • Re: Re: Getting the value of the independent var from the dep.var using NDSolve
    • From: Pratik Desai <pdesai1@umbc.edu>