Re: [R] nls.lm

2016-10-23 Thread Mike meyer
. I look forward to the results. Best regards, Michael unaffiliatd > Gesendet: Freitag, 21. Oktober 2016 um 09:39 Uhr > Von: "Berend Hasselman" <b...@xs4all.nl> > An: "Mike meyer" <1101...@gmx.net> > Cc: ProfJCNash <profjcn...@gmail.com>

Re: [R] nls.lm

2016-10-20 Thread Mike meyer
sue. For that reason it is (in my view) a bad idea to force the user to set up his problem in R-model notation. Michael unaffiliated > Gesendet: Donnerstag, 20. Oktober 2016 um 15:26 Uhr > Von: ProfJCNash <profjcn...@gmail.com> > An: "S Ellison" <s.elli...@lgcgroup.com>, &

[R] nls.lm

2016-10-19 Thread Mike meyer
How do you reply to a specific post on this board instead of the thread? I am too incompetent to find this out myself. Thanks, Michael unaffiliated __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see

[R] nls.lm

2016-10-19 Thread Mike meyer
And finally, to put to rest the notion that the number of residuals is in any way significant for the solution of the least squares problem I submit to you the function f(x,y)=(x²+y²)² of 2 variables but only one residual f_1(x,y)=x²+y² which nonetheless has a unique minimum at the point

[R] nls.lm

2016-10-19 Thread Mike meyer
>From my reading of the above cited document I get the impression that the >algorithm (algorithm 3.16, p27) can easily be adapted to handle the case m 0 and so the system becomes ill conditioned. Why can we not get around this as follows: as soon as mu is below some threshold we solve instead

[R] nls.lm

2016-10-19 Thread Mike meyer
Make that f(x,u)=||x||². __ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal,

[R] nls.lm

2016-10-19 Thread Mike meyer
@SE: yes, not every system of equations with more variables than equations is solvable, we need an additional condition e.g. full rank of the coefficient matrix. Uniqueness of the solution was not required. @BH: Yes this is the document, it is a nice presentation. I did not read the first page

[R] nls.lm

2016-10-19 Thread Mike meyer
@pd: you know that a System of equations with more variables than equations is always solvable and if a unique solution is desired one of mimimal norm can be used. According to "Methods for nonlinear least squares problems" by Madsen, Nielsen and Tingleff the LM-algorithm solves Systems of the

[R] nls.lm

2016-10-19 Thread Mike meyer
Greetings, The description of nls.lm specifies that in minimizing a sum of squares of residuals the number of residuals must be no less than the dimension of the independent variable ("par"). In fact the algorithm does not work otherwise (termination code 0). But this condition is

[R] 32 and 64 bit R

2016-09-26 Thread Mike meyer
Hello,   I have both 32 and 64 bit verions of R installed. What happens if I open a workspace saved from 64 bit R in the 32 bit version or conversely? I am fairly careless but never noticed any problems.    __ R-help@r-project.org mailing list -- To