Displaying 20 results from an estimated 400 matches similar to: "Simple spectral analysis"
2005 Feb 10
5
Annual cumulative sums from time series
Hello world,
I am actually transferring a course in data management for
students in biology, geography and agriculture
from statistica to R - it works
surprisingly well. If anyone is interested in my scratch/notepad
(in German language), please see
www.hydrology.uni-kiel.de/~schorsch/statistik/statistik_datenauswertung.pdf
(pages 40-52)
The dataset is:
2013 Jan 22
1
How to assign time series to a vector with one leap year
Hello All,
I am trying to do the time series analysis in R and I want to assign a
vector as a time series. The data I provided is hourly. The data is from
Jan 1 2008 to Dec 31 2009. How can I assign the data such that the first
year is leap year and second is not ?
airtemp <- read.csv("airtemp.csv",header=T,sep="")
aw <- ts(airtemp,start=2008,frequency=8784,end=2009)
2006 Jan 31
1
How do I "normalise" a power spectral density
I have done a fair bit of spectral analysis, and hadn't finished collecting my thoughts for a reply, so hadn't replied yet.
What exactly do you mean by normalize?
I have not used the functons periodogram or spectrum, however from the description for periodogram it appears that it returns the spectral density, which is already normalized by frequency, so you don't have to worry about
2008 Mar 27
6
help! - spectral analysis - spec.pgram
Can someone explain me this spec.pgram effect?
Code:
period.6<-c(0,0,0,0,0,10,0,0,0,0,0,10,0,0,0,0,0,10,0,0,0,0,0,10,0,0,0,0,0,10
,0,0,0,0,0,10,0,0,0,0,0,10,0,0,0,0,0,10,0,0,0,0,0,10,0,0,0,0,0,10)
period.5<-c(0,0,0,0,0,10,0,0,0,0,10,0,0,0,0,0,0,10,0,0,0,0,10,0,0,0,0,0,0,10
,0,0,0,0,10,0,0,0,0,0,0,10,0,0,0,0,10,0,0,0,0,0,0,10,0,0,0,0,10,0)
par(mfrow=c(2,1))
2024 Jul 10
1
Implementation for selecting lag of a lag window spectral estimator using generalized cross validation (using deviance)
Dear All,
I am looking for:
A software to select the lag length for a lag window spectral estimator.
Also, I have a small query in the reprex given below.
Background for the above, from the book by Percival and Walden:
1. We are given X_1,...,X_n which is one realization of a stochastic process.
2. We may compute the periodogram using FFT, for example by the
function spectrum in R.
3. The
2011 Jul 11
1
Spectral Coherence
Greetings,
I would like to estimate a spectral coherence between
two timeseries. The stats : spectrum() returns a coh matrix
which estimates coherence (squared).
A basic test which from which i expect near-zero coherence:
x = rnorm(500)
y = rnorm(500)
xts = ts(x, frequency = 10)
yts = ts(y, frequency = 10)
gxy = spectrum( cbind( xts, yts ) )
plot( gxy $ freq, gxy $
2006 Jan 27
2
How do I "normalise" a power spectral density analysis?
Hi everyone
Can anyone tell me how I normalise a power spectral density (PSD) plot of a
periodical time-series. At present I get the graphical output of spectrum VS
frequency.
What I want to acheive is period VS spectrum? Are these the same things but the
x-axis scale needs transformed ?
Any help would be greatly appreciated
Tom
2017 Oct 12
2
dual y-axis for ggplot
Hi,
To my knowledge, an excellent of ggplot with a second y-axis is
https://rpubs.com/MarkusLoew/226759
In this example, the author uses two colors for the two lines, but the
line shapes are the same -- both are solid. Could each line have its own
color as well as its own shape? For example, can I make the red line with
the linetype "twodash", while the blue line with the
2017 Oct 12
0
dual y-axis for ggplot
Sorry let me clarify.
If I modify the line
p <- p + geom_line(aes(y = air_temp, colour = "Temperature"))
by
p <- p + geom_line(aes(y = air_temp, colour = "Temperature", linetype
="Temperature"))
and
p <- p + geom_line(aes(y = rel_hum/5, colour = "Humidity"))
by
p <- p + geom_line(aes(y = rel_hum/5, colour = "Humidity",
2004 Aug 24
7
Strange update problem 3.0.5->3.0.6 with XP-Clients
Hello world,
I have a very strange update problem: this night I upgraded
from 3.0.5 to 3.0.6 (debian unstable) and the system broke completely
with very strange errors (I did not change anything to smb.conf)
- win98 users can log in, copy and everything
- xp users can log in, they see the shares but they cannot access
the files (read error in xp). I have tested it with
Xp-Prof SP1 und SP2
2017 Oct 12
1
dual y-axis for ggplot
Hi John,
You can try the following:
override.linetype=c("twodash","solid")
p <- ggplot(obs, aes(x = Timestamp))
p <- p + geom_line(aes(y = air_temp, colour = "Temperature", linetype
="Temperature"))
p <- p + geom_line(aes(y = rel_hum/5, colour = "Humidity",
linetype="Humidity"))
p <- p +
2002 May 17
1
Spectral Analysis
Dear R users
Is there a function in R to make a peridogram for
a spectral analysis of unevenlly sampled data??
something like spec.lomb() for S-Plus??
How to plot a vector with unequally spaced time series??
e.g
day/month/year V1
03/08/82 0.34
28/08/82 1.42
12/09/82 0.28
20/09/82 0.56
03/10/82 0.85
21/10/82 1.45
thanks
--
Marcelo Alexandre Bruno - Pos-graduacao Oceanografia Biologica
2005 Feb 17
4
Getting *types* of arguments?
Hello world,
short question: is there a possibility to get a list of
arguments of a function *with* variable/parameter types?
formals() gives me the names of the parameters, but says
nothing about the parameter type it expects (I know I can always use the
help function).
I would like somthing like
$x: vector or data.frame...
Thanks in advance...
Georg
--
Georg Hoermann, Fachabteilung
2012 May 30
1
caret() train based on cross validation - split dataset to keep sites together?
Hello all,
I have searched and have not yet identified a solution so now I am sending
this message. In short, I need to split my data into training, validation,
and testing subsets that keep all observations from the same sites together
? preferably as part of a cross validation procedure. Now for the longer
version. And I must confess that although my R skills are improving, they
are not so
2006 Jan 24
3
R-help Digest, Vol 35, Issue 24
Dear Prof Ripley,
First of all, unless you are an english professor, then I do not think you have
any business policing language. I'm still very much a student, both in R, and
regarding signal analysis. My competence on the subject as compared too your
own level of expertise, or my spelling for that matter, may be a contension for
you, but it would have been better had you kept that opinion
2010 Nov 22
1
cpgram: access data, confidence bands
Dear R experts, beginners and everyone else,
I'm calculating "cumulative periodogram" using the command "cpgram"
[1] from the MASS library. Here is a short example with the "lh"
(hormone level) dataset:
library(MASS)
plot(lh,type="l",ylab="value",xlab="time", main="Hormone Levels (lh)")
spectrum(lh,
2003 Jul 28
5
DVD Drive wont mount
Hi, I am having trouble using my dvd drive in KDE, as it wont mount, using dvd, cd, cdrw. all I get is the error message saying:
Could not mount device.
The reported error was:
cd9660: /dev/acd0: Invalid argument
Has anyone got a solution for this?
Thanks,
Brian
2012 Oct 13
1
Question about printing
Hello all,
is it possible to print from a linux box to a printer, shared on a
windows 7 box?
In Windows 7 the Administrator account is deactivated without a password
in default.
Have i to enable the account?
Have i to set a password?
Thanks
2007 Jul 09
1
When is the periodogram is consistent with white noise?
Hello everyone,
This is my first time posting to the list, thanks in advance.
I am calculating the smoothed periodogram for the residuals of an AR model
that I fit to EEG data. The autocorrelation plot of the residuals shows the
series is now approximately white (i.e. ACF = 1 at lag 0, and close to 0 for
all other lags). I would like to show that the spectrum of the series is
also
2008 Jul 21
2
Time Series - Long Memory Estimation
Dear R-Users,
I am doing a research on Time Series, especially on the estimation of the
fractional exponent in long memory time series (for those who know).
However there are three estimators already built-in the fracdiff package
(GPH, Sperio, MLE)
I was wondering if there is someone who had used an estimation introduced by
P.M. Robinson (related paper: "Log-Periodogram regression of time