Hi,

Excuse me for asking this silly question. But I really couldn't understand
why cov() and ccov() don't work for my calculation of covariance matrix.

a <- matrix(1:8, 2, 4)
a
     [,1] [,2] [,3] [,4]
[1,]    1    3    5    7
[2,]    2    4    6    8
> ccov(a)
Error in solve.default(cov, ...) :
  Lapack routine dgesv: system is exactly singular
I also tried colume bind, but it still doesn't work.
> a1<- a[,1]
> a2 <- a[,2]
> a3<- a[,3]
> a4 <- a[,4]
> acomb <- cbind(a1,a2,a3,a4)
> acomb
     a1 a2 a3 a4
[1,]  1  3  5  7
[2,]  2  4  6  8
> ccov(acomb)
Error in solve.default(cov, ...) :
  Lapack routine dgesv: system is exactly singular
Yesterday, I used cov(), my function worked well. But today I ran the same
code, it returned an error like:

cov(td12)
Error in solve.default(cov, ...) :
system is computationally singular: reciprocal condition number =
1.97276e-24
In addition: Warning message:
'cov' is deprecated.
Use 'ccov' instead.
See help("Deprecated")
I don't know what is wrong, and I appreciate you kind help! Thank you!

Wendy

        [[alternative HTML version deleted]]

______________________________________________
R-help@r-project.org 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.

Reply via email to