Displaying 20 results from an estimated 2000 matches similar to: "Indexing and partially replacing 99, 999 in data frames"
2005 Nov 04
1
problem in waveslim library?
This code consistenly segfaults for me. Can someone please take a look
and tell me if the problem is due to something I am doing or is there a
problems with the dwt (idwt) functions in the waveslim library.
Thanks
tom
library(waveslim)
2012 Mar 17
3
how to call functions with same name but in different package?
hi everyone .
I am trying to use some packages but there are some functions have the same
name in different package.
for example
dwt function
both in packages wavelets and waveslim
dwt(X, filter="la8", n.levels, boundary="periodic")
How can I avoid mixing them up ?
--
TANG Jie
Email: totangjie@gmail.com
Tel: 0086-2154896104
Shanghai Typhoon Institute,China
2006 May 25
1
understanding DWT
Can someone please help me understand the examples given in the dwt
function of the waveslim library
library(waveslim)
?dwt
I'm having a problem understanding these lines. I assume they are
required because of how the algorythm deals with the signal bounderies.
Am I correct in thinking that for wavelets of scale 1 and 2, the
coefiecints need to be shifted by 2 places, for scale 3 and 4 shift
2009 Oct 16
2
what's the R code for wavelet decomposition (Haar transformation)?
Dear all,
Using R function "dwt", it seems that I cannot specify the wavelet
transformation like Haar. What's the R code for wavelet decomposition
which allows me to specify Haar wavelet transformation? Of course, if it
can include "db2", that is even better. In general, I want an R function
like matlab code "dwt". Thanks in advance!
Zhen Li
2001 Nov 09
1
Installing packages
Hello,
I have upgraded from Mandrake Linux 8.0 to Mandrake 8.1 and try to reinstall
my favourite R... Everything is OK for the base software but I have trouble
to get some packages installed.
Specifically, for some packages, a "collect2" binary seems to be necessary
during the compilation/linking process of the library, and LD complains about
not finding it :
Installing source
2010 Dec 22
1
tests on polr object
Using ordered probit model, I get errors from dwt and bptest.
dwt:
Error in durbinWatsonTest.default(...) : requires vector of residuals
bptest:
Error in storage.mode(y) <- "double" :
invalid to change the storage mode of a factor
I imagine I have to restate as an individual probit model for each category,
but is there an easier way?
thanks,
bp
[[alternative HTML version
1999 Nov 19
2
Impulses
After playing with the vorbis code for a while and doing tons of hacks and
analysis on it, I've found it to perform very poorly with impulse signals.
The MDCT seems to cause lots of spreading, and it seems to result in much
worse impulse performance then mp3.
What is the current plan on handling this? Will a smart quantizer be able
to avoid it?
I've been looking at various ways of
2006 Jan 08
2
Filters in waveslim
Dear R Users,
For running wavelet functions using dwt( ), modwt( ), and mra( ), a wavelet filter algorithm is applied. For all these functions, default is "la8" and other possibility is "haar". In related documents, another possibilities like as symlet and coiflet ... are not cited.
Besides "la8" and "haar", which wavelet filters can be used?
Thank
2010 Aug 04
1
wavlet transform
Hello
I do wavelet transform by using this code:
dec=dwt(ld, filter='d8', n.levels=lev, boundary="reflaction");
dec consists of the decomposition coefficients and other
How can I change the coefficients the decomposition manualy?
--
View this message in context: http://r.789695.n4.nabble.com/wavlet-transform-tp2313427p2313427.html
Sent from the R help mailing list archive at
2011 Sep 27
1
two-way anova help
Hello,
I am having some trouble coding a two-way anova due to replicated
treatments.
I have a factorial design with three male parents and three female parents.
They were mated in all combinations and their babies were grown out and
measured for size. 50 babies were measured for each of the 9 crosses. If I
stopped here, I would have no troubles. But I also have 5 replicate tanks
for each of
2002 Oct 27
1
denoising univariate data with wavelets
Hi,
I am interested in a applying wavelets as a smoothing tool for my
(1-dimensional) data. I looked into wavetresh and waveslim packages but
could not quite figure out an obvious way to do this after running dwt or
wt functions. Would someone be able to point me in the right direction on
how to denoise univariate data using one of wavelet packages available in
R?
Thank you very much
Jane
ps
2012 May 30
1
Help needed for this error
> results <- mra(x$w1mcp, filter = "d4", n.levels = 3, boundary =
"periodic", method = "dwt")
> write.csv(results, "c:/mydata.csv")
Error in as.data.frame.default(x[[i]], optional = TRUE) :
cannot coerce class 'structure("mra", package = "wavelets")' into a
data.frame
I am not able to access data stored in results.
2008 Dec 28
0
how to calculate DWT maximum decomposition level
Given a time series of length N, I am trying to figure out its maximum DWT decomposition level.
With reference to "dwt" function of R package "wavelets", running the provided example I get the following
and wonder how the maximum decomposition level (which is not an integer number) is calculated.
I tried myself the formula in the on-line documentation but could not get the
2001 Nov 03
3
Vorbis 1.0 before the end of the year?
Hi guys.
IMO now it's definitely time for finalizing Vorbis and throwing it
in the arena.
Two reasons:
- RC2 sounds wonderfully well, I'm really amazed how good it is..
and I personally think there's little room for further improvement in
sound quality..
- portable music devices are starting to take off (see Waitec, Creative,
Apple and many other vendors).
Wouldn't be good
2017 Jun 27
0
paste strings in C
To do this in C, it would probably be easier and faster to just do the
string manipulation directly. Luckily, there are already packages that
have done this for you. See an example below using the S4Vectors
package.
foo2 <- function(mymat, colnms, tilde=FALSE) {
chars <- colnms[col(mymat)]
lowerChars <- if (tilde) paste0("~", chars) else tolower(chars)
chars <-
2004 Mar 14
3
Weird quirk with ingress policing
Hi,
I notice that if two or more existing connections match an ingress
policing filter, the input bandwidth does not get evenly divided up
between the n connections.
Kinda like litters of baby animals, where the stronger babies get more
access to the mothers teats and grow up bigger and faster than their
siblings.
The only workaround that''s working for me is to set explicit ingress
2009 Feb 24
0
Wavelet Bootstrap Size Simulation
I have written a short script to estimate the size of a test of non-constant
mean in an AR(1) time series. When I run the simulation on my PC (R version
2.7.1), I get the expected result: an empirical size much larger than the
nominal size. On the Red Hat machine (R version 2.7.2) in my department,
however, I get p-values > .45 for every simulated test. Below is my
simulation code (uses
2011 Oct 01
1
class definition
Hi everybody!
I have a matrix of class "myClass", for example:
myMat <- matrix(rnorm(30), nrow = 6)
attr(myMat, "class") <- "myClass"
class(myMat)
When I extract part of ''myMat'', the corresponding class ''myClass'' unfortunately disappear:
myMat.p <- myMat[,1:2]
class(myMat.p)
Please for any advice / suggestions, how
2017 Jun 27
2
paste strings in C
Dear R-devs,
Below is a small example of what I am trying to achieve, that is trivial in
R and I would like to learn how to do in C, for very large matrices:
> (mymat <- matrix(c(1,0,0,2,2,1), nrow = 2))
[,1] [,2] [,3]
[1,] 1 0 2
[2,] 0 2 1
And I would like to produce:
[1] "a*C" "B*c"
Which can be trivially done in R via something like:
foo
2006 Mar 21
1
rownames, colnames, and date and time
I noticed something surprising (in R 2.2.1 on WinXP)
According to the documentation, rownames and colnames are character vectors.
Assigning a vector of class POSIXct or POSIXlt as rownames or colnames
therefore is not strictly according to the rules.
In some cases, R performs a reasonable typecast, but in some other cases
where the same typecast also would be possible, it does not.
Assigning a