Displaying 20 results from an estimated 2000 matches similar to: "R det"
2003 Nov 12
2
bug in det using method="qr" (PR#1244) (PR#4450)
I just detected, that det() is not working on complex matrices any more,
due to the fix to the bug reports noted above. I am not happy with this,
as determinants are perfectly usable on complex matrices.
AFAIUI the bugs resulted from less than optimal behaviour of qr() in
certain cases. IMHO this is due to the unhappy decision to use a default for
parameter tol to decide whether the the
2022 Nov 09
1
det(diag(c(NaN, 1))) should be NaN, not 0
Hello,
Currently, determinant(A) calculates the determinant of 'A' by factorizing
A=LU and computing prod(diag(U)) [or the logarithm of the absolute value].
The factorization is done by LAPACK routine DGETRF, which gives a status
code INFO, documented [1] as follows:
*> INFO is INTEGER
*> = 0: successful exit
*> < 0: if INFO = -i, the i-th
2005 Aug 16
1
Home directories on AD/Samba
I just set up our Samba-Server to athenticate over Active Directory
(Win 2003). But there is one thing that bothers me: There are no
home-directories for the domain users, that waere added to the linux
passwd database (EXAMPLE.COM+user1 can be authenticated, but has no
home on the Linux-box). If I create a share home, nobody can open it,
because it cannot be found. Only if I set the path option,
2003 Jul 21
1
URGENT! brandly new Wildcard E400P for sale at $1000
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Regards,
Kalin
-----------------------------
IPPN Networks
2002 Jan 05
1
possible bug in det using method="qr" (PR#1244)
Full_Name: Armin Roehrl
Version: 1.4.0(2001-12-19)
OS: Linux; Suse 7.3
Submission from: (NULL) (217.84.18.204)
Hello,
On a given matrix det returns different results whether
I use the method "qr" or "eivenvalues".
The matrix:
> m2
[,1] [,2] [,3]
[1,] 9.822616e+09 3.841723e+09 79790.09
[2,] 3.841723e+09 1.502536e+09 31251.82
[3,]
2010 Apr 13
1
Lapack, determinant, multivariate normal density, solution to linear system, C language
r-devel list,
I have recently written an R package that solves a linear least squares
problem, and computes the multivariate normal density function. The bulk
of the code is written in C, with interfacing code to the BLAS and
Lapack libraries. The motivation here is speed. I ran into a problem
computing the determinant of a symmetric matrix in packed storage.
Apparently, there are no explicit
2009 Oct 19
1
overloading base function
Hello,
I am trying to write an R package for doing analysis of speaker
recognition systems. The big thing in this line of research is a
DET-plot (detection Error Trade-off, a ROC plot with qnorm() warped
axes). My approach has been to make a class "det" and also a
function "det()" that will prepare the data into the right class.
Now loading the library doesn't like me
2003 Oct 07
1
(PR#4450)
Hello,
When I use det() and qr() on complex matrices the result is in some cases indeterministic. The documentation speaks of numeric matrices (and not of complex matrices) but det() uses qr() which should handle complex matrices correctly. I've also tried using only qr() with
similar results. det() returns a value that is not the determinant of the complex matrix (in accordance with
2006 Sep 26
2
about the determinant of a symmetric compound matrix
Dear R users,
even if this question is not related to an issue about R, probably some of you will be able to help me.
I have a square matrix of dimension k by k with alpha on the diagonal and beta everywhee else.
This symmetric matrix is called symmetric compound matrix and has the form
a( I + cJ),
where
I is the k by k identity matrix
J is the k by k matrix of all ones
a = alpha - beta
c =
2006 Jul 06
1
ASCII colors in MOTD
Hi all,
For some time I noticed that my rsync server is not showing a colorfull MOTD...
Researching a bit, it turns out to be a problem since rsync-2.6.7 (rsync-2.6.6 is OK).
Looking at the NEWS:
- The way rsync escapes unreadable characters has changed. First, rsync
now has support for recognizing valid multibyte character sequences in
your current locale, allowing it to
2006 Nov 07
4
solve computationally singular
Hi uRsers,
when inverting a 2 by 2 matrix using solve, I encountered a error message:
solve.default(sigma, tol = 1e-07) :
system is computationally singular: reciprocal condition number
= 1.7671e-017
and then I test the determinant of this matrix: 6.341393e-06.
In my program, I have a condition block that whether a matrix is
invertible like this:
if(det(sigma)<1e-7) return NULL;
2007 Jun 01
1
Determinant function (PR#9715)
Full_Name: Krzysztof Podgorski
Version: R version 2.4.1 (2006-12-18)
OS: Windows XP
Submission from: (NULL) (130.235.3.79)
The function ''det'' works improperly for a singular matrix and returns a
non-zero value even if ''solve'' reports singularity. The matrix is very simple
as shown below.
A <- diag(rep(c(64,8), c(8,8)))
A[9:16,1] <- 8
A[1,9:16] <- 8
2003 Aug 09
2
[Bug 623] ssh, ssh-keygen and possibly others do not honour $HOME
http://bugzilla.mindrot.org/show_bug.cgi?id=623
Summary: ssh, ssh-keygen and possibly others do not honour $HOME
Product: Portable OpenSSH
Version: 3.6.1p2
Platform: All
OS/Version: Linux
Status: NEW
Severity: normal
Priority: P2
Component: ssh
AssignedTo: openssh-bugs at mindrot.org
2011 Aug 02
1
Functions for Sum of determinants of ranges of matrix subsets
Dear R-help list,
Pls I have this problem. Suppose I have a matrix of size nxn say, generated as follows
z<-matrix(rnorm(n*n,0,1),nrow=n)
I want to write a function such that for i in 1:n, I will remove the rows and columns
corresponding to i (so, will be left with n-1*n-1 submatrix in each cases). Now I need
the sum of the determinant of each of this submatrices. As an example, if n=3, it
2017 Jan 18
3
Taking determinant of a matrix of NAs results in intermittent memory corruption
Greetings; I've posted the following to R's bug tracking system (at https://bugs.r-project.org/bugzilla/show_bug.cgi?id=17210 ) and Martin Maechler requested that I post to this list as well.
If I start R from the command line with --vanilla, then repeatedly execute the following line:
det(matrix(nrow=10,ncol=10))
... I eventually get a crash, with error:
*** Error in
2011 Mar 16
2
Singularity problem
Dear R,
If I have remembered correctly, a square matrix is singular if and only if
its determinant is zero. I am a bit confused by the following code error.
Can someone give me a hint?
> a <- matrix(c(1e20,1e2,1e3,1e3),2)
> det(a)
[1] 1e+23
> solve(a)
Error in solve.default(a) :
system is computationally singular: reciprocal condition number = 1e-17
Thanks in advance!
Feng
--
2004 Apr 15
5
Solving Matrices
On April 15th, Elizabeth wrote:
<snip>
> In execises 39-42, determine if the columns of the matrix span
> R4:
<snip>
>(or x <- matrix(data=c(7, -5, 6, -7, 2, -3, 10, 9, -5,
> 4, -2, 2, 8, -9, 7, 15), nrow=4, ncol=4)
>
>That is the whole of the question <snip>
Have you tried det(x) and/or eigen(x) ?
A zero determinant (within
2011 Jan 16
1
\examples{} in Rd file
[Hope this is the right list where to send...]
An attempt to update package 'mnormt' involves the addition of a
small new function called 'pd.solve'. When I come to the package
checking stage, an error occurs in parsing pd.solve.Rd.
The full transcript of the outcome is copied below (it includes details
on my installation) but the critical point is where the \examples{}
section
2012 Feb 27
1
Identical copy of base function
Hello,
Regarding this in R-devel/NEWS/New features :
o ?library(pkg)? no longer warns about a conflict with a function from
?package:base? if the function is an identical copy of the base one but
with a different environment.
Why would one want an identical copy in a different environment? I'm
thinking I may be missing out on a trick here.
Matthew
2004 Nov 18
1
Method dispatch S3/S4 through optimize()
I have been running into difficulties with dispatching on an S4 class
defined in the SparseM package, when the method calls are inside a
function passed as the f= argument to optimize() in functions in the spdep
package. The S4 methods are typically defined as:
setMethod("det","matrix.csr", function(x, ...) det(chol(x))^2)
that is within setMethod() rather than by name before