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nonlinear equation solver?

4 messages · Wang, Zhu, Murray Jorgensen, Spencer Graves +1 more

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Dear R-Help,
 
I am trying to use R to solve a nonlinear equation many times for different values. I am looking for a mathematical nonlinear equation solution which may not have a closed solution form. For example, I have equation:
2 = (t^2)/log(t)
What is t?
 
I am wondering how to solve it in R.
Many thanks,
 
Zhu Wang
 
Statistical Science Department
SMU.
#
For this equation you are out of luck as log(z) < z for all positive z's 
(such as t^2). More generally you should consult a numerical analysis 
textbook for advice on the solution of nonlinear equations. There you 
will read about many algorithms in common use by statisticians.

Murray Jorgensen
Wang, Zhu wrote:

  
    
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You may also wise to consider a book on nonlinear regression such as 
Bates and Watts (1988) Nonlinear Regression Analysis and Its 
Applications (Wiley).

hope this helps. spencer graves
Murray Jorgensen wrote:
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I think what you are looking for is uniroot().

-roger
_______________________________
UCLA Department of Statistics
http://www.stat.ucla.edu/~rpeng
On Sun, 20 Apr 2003, Wang, Zhu wrote: