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Todd Topley
07/18/13 07:27am

I am new to mathematica and need help setting limits/ranges/constraints on some vaiables i am using.

I am defing a data set
LogPD = {{4.57, 1.39}, {5.60, 1.67}, {6.36, 1.79}, {7.13, 2.30}, {8.00, 3.18}}

I would like use two variables but limit their ranges to between 2 and 12
pH = Range[2, 10]
pKa = Range[2, 10]

I am then using the data set and variables in a find fit
FindFit[LogPD, LogP - Log[1 + 10^(pKa - pH), 10], {LogP, pKa}, {pH}]

however I get this error:
FindFit::ivar: {2,3,4,5,6,7,8,9,10} is not a valid variable.

Then I would like to use the same equiation in a manipulate feature to vary the pKa and pH to best fit the line to that data set.
Show[Plot[LogP + Log[1 + 10^(pKa - pH), 10], {pH, 2, 11}, PlotRange -> {0, Vert}], ListPlot[LogPD, PlotRange -> {0, Vert}, PlotStyle -> Directive[Red, PointSize[0.02]]]], {LogP, 0,
10}, {Vert, 6, 100}, ControlPlacement -> Left]

Again, I am new to this and would appreciate any guidance and assistance.

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Subject (listing for 'define/limit variable ranges')
Author Date Posted
define/limit variable ranges Todd Topley 07/18/13 07:27am
Re: define/limit variable ranges Bill Simpson 07/19/13 11:40pm
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