search for: sinusoidal

Hello, I will try to explain the problem, sorry if it will be a little long... I'm using R to analyze results of cyclic mechanical testing, like this: - apply quasi-sinusoidal load - measure quasi-sinusoidal vertical and horizontal deformations (quasi-sinusoidal load means that load "should be" sinusoidal, but testing machine puts in some noise...) I enclose a sample of data at the end of this message. I used harmonic regression to fit the data: force = con...

Hi, Suppose x and y are vectors whose elements are known. I know that there is a sinusoidal relation between them. In other words, y=a*sin(bx) where b is probably a function of pi. How do I find a and b in R? Hakan [[alternative HTML version deleted]]

On Thu, 2005-01-13 at 12:42 -0500, Jean-Marc Valin wrote: > Le jeudi 13 janvier 2005 ? 10:59 -0500, Jared Whitby a ?crit : > > Interestingly enough.. I started playing around with preprocessing > > options in 1.1.6 and happened upon the denoise filter > > (SPEEX_PREPROCESS_SET_DENOISE). When i run the test tone using that > > option it is completely filtered out and I

Hello, In doing a series of non-linear estimations of a function which is a sum of a varying number of sinusoids, I would like to "autogenerate" the arguments needed by nls() depending on that number. For example, when there are two sinusoids: > nls( y ~ mu + A1 * cos(2*pi*f1*x - P1) + A2 * cos(2*pi*f2*x - P2), data = some.xy.data, start = list( mu=some.value0,

Dear List, I am attempting to perform a harmonic analysis on a time series of snow depth, in which the annual curve is essentially asymmetric (i.e. snow accumulates slowly over time, and the subsequent melt occurs relatively rapidly). I am trying to fit a curve to the data, however, the actual frequency is unknown. I have been trying to follow the methods in Peter Bloomfields text

Dear all, Before I can get into serious Fourier analysis of Radon time-series I am practising with 24hour and 24.8hour sinusoids to assist with my interpretation of signals ittributed to tidal input to Radon time series. I am stuck. I have tried researching this to no avail. I am awating a book that should describe fourier transforms in detail and another one that should discuss the R

...nothing so far. If I am unable to find an existing R package to do so, is there anyone familiar with fitting sine functions to data. My problem is this: I have a long time-series of daily SWE estimates (SWE = snow water equivalence, or the amount of water stored in a snowpack) which follows a sinusoidal pattern, and I need to estimate the parameters of the sine function that best fits this data. While there may be many contributing sine functions and/or linear trends, I am only interested in a single sine function that most closely fits the data (trends can be removed separately if need be)....

Well I think a sinusoid shouldn't totally trash the encoder state, so I still think theres a bug lurking around in there. The denoiser just prevents it from ever making it to the encoder. Just from browsing through the speex code and from what I've learned reading through the mailing list, it looks like there are a few places where checks are in place to prevent sinusoids from

Hello, I'm working on a very large project in which we do many calculations which include many types of regression such as, Liner, Quadratic, Cubic, Exponential, Sinusoidal, and Logarithmic. Im well aware that its easy enough to do Linear regression in R but what about the other types? I've been searching on google for such functions but to no avail. Thank you, -- Samuel Bravo Department of Computer Science The University of Texas at El Paso El Paso, TX 79968...

Hello list, I am making scatterplots of data that vary sinusoidally over 24 hours. With a bit of previous help from this list, I now can get an x-axis with time tics from 00:00 on the left edge to 12:00 in the middle and 00:00 on the right edge, i.e., just 24 hours. Now I would like to fit a sin function to the plot. I've looked all over CRAN and the web...

well if you want to find the spectral density aka what frequencies explain most of the variance then I would suggest the spectral density. This can be implemented with spec.pgram(). This is conducted with the fast fourier transform algorithm. a<-ts(data, frequency = 1) #make the time series with 365readings/365days ?spec.pgram and you should be able to take it from here This will

Hi Guys, I had a monthly time series's data of land temperature from 1980 to 2008. After plotting a scatter diagram, it seems that annually, there is a semi sinusoidal cycle. How do I run Fourier's series to the data so that I can fit model on it? I am really sorry for my question sound stupid, but I just don't know where to start. I am desperately looking for help from you guys. Thanks in advance. Eddie [[alternative HTML version deleted]]

I have a vector with about 100.000 values representing a quite regular function (sinusoid like). I would like to find all local maxima of this function (should be about 4000). Is there a native routine for R? Thanks in advance Eryk. -- _|_ \|/ \|/ Eryk Witold Wolski tel :0049-(0)30-8413-1543 w w ?v? 'v? \'v'/ MPI Moleculare Genetik fax :0049-(0)30-8413-1139 |

Hi, Are there any functions in R that could be used to estimate the phase-shift between two semi-sinusoidal vectors? Here is what I have tried so far, using the spectrum() function -- possibly incorrectly: # generate some fake data, normalized to unit circle x <- jitter(seq(-2*pi, 2*pi, by=0.1), amount=pi/8) # functions defining two out-of-phase phenomena f1 <- function(x) jitter(sin(x), amount...

Hello, I requested help a couple of weeks ago creating a dipole field in R but receieved no responses. Eventually I opted to create a 3d sinusoidal plot and concatenate this with its inverse as a means for a "next best" situation. It seems that this isn't sufficient for my needs and I'm really after creating a continuous 3d gaussian mesh with a "positive" and "negative" dipole. Can anyone offer any pointe...

Interestingly enough.. I started playing around with preprocessing options in 1.1.6 and happened upon the denoise filter (SPEEX_PREPROCESS_SET_DENOISE). When i run the test tone using that option it is completely filtered out and I just get (complete) silence. When the test tone is intermixed with regular voice I only get the voice. So while i still don't quite understand why the test tone

Hi I have a Dell PowerEdge T310 *tower* server.. I have to buy an ups by apc... anyone could help me giving an hint ? a simple "smart ups 1000" could be enough ? thx so much!! lewis.

...thematic map of the USA. My problem is that cracks (white spaces) appear between some states--e.g. between Colorado and Utah and between Michigan and Indiana. The resulting visual impression is that the country is breaking up. This occurs in all the projections I have tried: albers, mercator, sinusoidal. An example of a command producing this effect is the following: map("state", regions=names48, projection="albers", par=c(36, 53), fill=T, col=rgb(red, green, blue, maxColorValue=255)) Suggests for filling the cracks would be very welcome. -John -- John P. Burkett Department...

Hello, I have daily wind speed data and need to fit seasonal ARIMA model, problem is that my period is 365. But when I use arima(...) function, with period 365, I?m getting error message: ?Error in makeARIMA(trarma[[1]], trarma[[2]], Delta, kappa) : maximum supported lag is 350?. Can someone help me with this problem? Thank you Sincerely yours, Laura Saltyte

Hello, the only thing I found to fit a sin/cos is s.th like lm(a~cos+sin) But this is not what I want. I have a magnitude which is sinusoidal with offset and it doesn't start at phi=0. The data is: angle<-c(0,10,20,30,40,50,60,70,80,90,100,110,120,130,140,150,160,170,180) Voltage<-c(-45.07, -45.24, -43.61, -40.78, -36.48, -30.92, -23.83, -15.95, -7.53, 1.06, 11.24,19.85, 27.00, 35.00, 42.90, 49.41, 54.62, 58.54, 60...