while doing curve-fitting for custom equation, error is occuring??

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iam doing a custom equaion in curve-fitting tool to find the constants.
y= c+a*log(x)+b*log(1-x) it is the equation. I took more x and y points to plot the graph. Then also "" Inf computed by model function, fitting cannot continue.
Try using or tightening upper and lower bounds on coefficients"" this error is occuring when i entered the equation. Please help me out to clear this error and to get constants??
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Answers (1)

Jakob B. Nielsen
Jakob B. Nielsen on 13 Feb 2020
Edited: Jakob B. Nielsen on 13 Feb 2020
If your input data contains or spans x=0, your first logaritm will not be defined. In addition, if your x exceeds 1, your second logaritm log(1-x) will be a complex number, and therefore can't be fitted - while it, again, will not be defined for x=1.
Make sure your x input lies between 0 and 1, but not containing either.

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