see inline below. On Tue, Feb 1, 2011 at 2:25 PM, Mike Marchywka <[email protected]> wrote: > > > > >>Date: Tue, 1 Feb 2011 15:41:01 +0000 >>From: [email protected] >>To: [email protected] >>CC: [email protected]; [email protected] >>Subject: Re: [R] Positive Definite Matrix > > >>Hello thank you for so much input. I am afraid that I am fairly new to this > and some of the material is above my understanding for the time being and I > am not looking at anything very complex as you will see from the program I > will include. > I have been talking to a fellow colleague I am working with and have come > down to this. > Your input has been invaluable to me learning more about R thank you! > 1.As an example, I do not wish to find a near pd matrix but I want to test > wether it is pd or not so I know if I want it or not,as you will see on the > program I want two outputs depending on if it is a pd and symmetric. So I > have written this for one symmetric matrix and it works and one for a non > symmetric one slightly changed but it doesnt work,if you could point out why > this is going wrong that would be helpful. It cant compare the complex > eigenvalues. > [...] > >>2. My colleague said why dont we use the Sylvester's Criterion and test the > leading minors. Would something like that work?
It would work, but it would be more work than just testing the eigenvalues! kjetil > > > This thread seems to have dragged on for a while, what are you trying to do? > Presumably this is something other than an exercize in R. > What interpretation do you have for your eignenvalue spectrum or matrix > element > ? Problems here could point to various features or pathologies or > opportunities at various points in the analysis. > > > > > > ______________________________________________ > [email protected] mailing list > 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, self-contained, reproducible code. > ______________________________________________ [email protected] mailing list 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, self-contained, reproducible code.
