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Question: NonlinearFit initial value

Question:NonlinearFit initial value

gcarlson 36 Maple
June 06 2009
0
<p>I running Maple 12. I don't see what could be wrong with the specified initial values for this nonlinear fit problem. Note error when initial vlaues are specified, and no error without initial values. > XY := Matrix([[1, 5],[2, 7],[3,10],[4,17],[5,24],[6,37]], datatype=float): > initxy := Vector([1,2,3], datatype=float): > Z := Vector([2.2, 3, 4.8, 10.2, 24.5, 75.0], datatype=float): > NonlinearFit(exp(a+b*x+c*y), XY, Z, [x,y],initialvalues=initxy); Error, (in Statistics:-NonlinearFit) invalid input: no implementation of NonlinearFit matches the arguments in call, NonlinearFit(exp(a+b*x+c*y),op(w),[x, y],initialvalues = (Vector(3, [...], datatype = float[8]))) > NonlinearFit(exp(a+b*x+c*y), XY, Z, [x,y]); exp(-0.209656785380510162 + 0.413711750400883371 x + 0.0552760194520834567 y) Is there something wrong with how I specified the vector of initial values? "Help" tells me that "initialvalues = ... Vector(realcons) -- Provide initial values for the parameters." Not shown here is the initxy vector works fine in the matrix form of NonlinearFit. Thanks for any assistance. Glenn</p>
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