Displaying 20 results from an estimated 290 matches for "amplitude".
2006 Jul 31
0
Three questions about a model for possibly periodic data with varying amplitude
...is two-fold: firstly, I need to test for periodicity, and
secondly, I need to try to predict the temporal location of future
peaks. Of course, the peaks might be occurring on unmeasured days.
I have been looking at this model:
wave.form <-
deriv3( ~ sin(2*pi*((day-offset)/period + 0.25)) * amplitude + mean,
c("period", "offset", "amplitude", "mean"),
function(day, period, offset, amplitude, mean){})
curve(wave.form(x, period=7, offset=2, mean=5, amplitude=4),
from=1, to=30)
So, for my purposes, the mean and the amplitude seem to...
2006 Jan 24
3
R-help Digest, Vol 35, Issue 24
...disorders, head injuries,
and/or vertigo.
On the contrary, I am aware of the definition of a periodogram, and I know what
the unnormalized periodogram in the data I presented looks like. Spec.pgram()
is actually normalized too something, because it's discrete integral is not
well above the SS amplitude of the signal it computed the periodogram for. In
other words, the powers are not in units of around 4,000, which the peak would
be if the units were merely the modulus squared of the Fourier coeficients of
the data I presented. Alas, the modulus squared of the Fourier coeficients IS
the TWO SIDED...
2003 Apr 14
2
categorical variables
...: int 1 1 1 1 1 1 1 1 1 1 ...
$ Reproducao : int 3 3 3 3 3 3 3 3 3 3 ...
$ Estacao : int 2 2 2 2 2 2 2 2 2 2 ...
$ X30cm : int 1 1 1 1 1 1 1 1 1 1 ...
$ Dir.mov : int 0 0 0 0 0 0 0 0 0 0 ...
$ Temp.media : num 12.0 11.3 12.1 12.3 12.4 ...
$ Temp.amplitude : num 1.167 -0.750 0.875 0.125 ...
$ Vel.media : num 0.479 0.514 0.517 0.445 0.468 ...
$ Vel.amplitude : num -0.04865 0.03417 0.00312 0.02364 ...
$ Caudal.medio : num 0.570 0.585 0.589 0.485 0.501 ...
$ Caudal.amplitude: num -0.04323 0.01449 0.00405 0.01617 ...
$ Prof.m...
2006 Jan 24
1
spec.pgram() normalized too what?
Dear list,
What on earth is spec.pgram() normalized too? If you would like to skip my
proof as to why it's not normed too the mean squared or sum squared
amplitude of the discrete function a[], feel free too skip the rest of the
message. If it is, but you know why it's not exact in spec.pgram() when it
should be, skip the rest of this message. The issue I refer herein refers
only too a single univariate time series, and may not reflect the issues
encounte...
2006 Aug 15
1
A model for possibly periodic data with varying amplitude [repost, much edited]
...##############
patient <- data.frame(
day = c(1, 3, 5, 8, 10, 12, 15, 17, 19, 22, 24, 26),
protein = c(5, 3, 10, 7, 2, 8, 25, 22, 7, 10, 12, 5)
)
plot(patient$day, patient$protein, type="b")
# This is my model:
wave.form <-
deriv3( ~ sin(2*pi*((day-offset)/period + 0.25)) * amplitude + mean,
c("period", "offset", "amplitude", "mean"),
function(day, period, offset, amplitude, mean){})
curve(wave.form(x, period=7, offset=2, mean=5, amplitude=4),
from=1, to=30)
require(nlme)
wave.1 <- gnls(protein ~ wave.f...
2011 Feb 08
1
Recuperate Spectrum() amplitude
Dear list,
I apologies first for my English, hope you will understand well my question.
I am working on 1/2 hour piezometric data, time unit is second. They
present daily oscillation when using the spectrum() function. What I am
really interested in, is to find the amplitude corresponding to this
oscillation.
I work with a college using Matlab, and although we apply the same
methodology, our results differs : we find the same frequencies, but not
the same amplitudes.
I put the code I use here to understand if the difference comes from the
way that fft function ar...
2009 Sep 17
2
Voice Playback cutting first word or so of audio file
...block align, 16 bits/samp, 146966 data
bytes
sox: 73483 Samps/chans
sox: Input file mysoundfile.wav: using sample rate 8000
size shorts, encoding signed (2's complement), 1 channel
Samples read: 73482
Length (seconds): 9.185250
Scaled by: 2147483647.0
Maximum amplitude: 0.980347
Minimum amplitude: -0.980347
Midline amplitude: 0.000000
Mean norm: 0.190652
Mean amplitude: -0.004612
RMS amplitude: 0.294026
Maximum delta: 1.554443
Minimum delta: 0.000000
Mean delta: 0.096981
RMS delta: 0.1636...
2010 Jun 09
0
Testing for differences in amplitude and phase
...ups. The seasonal variation can
be best described by two harmonics, I called the frequencies
omega and omega2.
I now want
to test whether (1) the seasonal pattern differs between the treatments (some
kind of overall test). If this is the case, (2) I want to conduct tests to find
out whether the amplitude of the fist harmonic, the amplitude of the second harmonic,
the phase of the first harmonic and the phase of the second harmonic differs
between the treatment groups.
My attempt
was to create a lme containing the two oscillations and the treatment group:
omegaDay=omega*Day #...
2010 Nov 04
1
About Acoustic Echo Canceller
Hello.
I'm from Federal University of Rio Grande do Sul - Brazil and I'm
trying to adapt
speex_echo.h (speex-1.2beta3-win32) to our video-conference software code.
We are working on amplitude values, but I realised that in order to AEC
works, one has to convert amplitude to frequency and filter the echo
frequencies. So, my question is:
Do I have to manually convert amplitude samples to frequency samples or is
it enough to send amplitude parameters to speex_echo.h functions that this
fu...
2017 Jun 25
2
Writing my 3D plot function
...adius 1 (in terms of simplicity) but unfortunately I have the cartesian coordinates legends that do not help on reading my Figure. You can help me by executing the code below?
require("rgls")
degreeToRadian<-function(degree){? return ? (0.01745329252*degree)}
turnPolarToX<-function(Amplitude,Coordinate){? return (Amplitude*cos(degreeToRadian(Coordinate)))}
turnPolarToY<-function(Amplitude,Coordinate){? return (Amplitude*sin(degreeToRadian(Coordinate)))}
# Putting the first circle on 3d space. Circle of radius 1X1<-turnPolarToX(1,1:360)Y1<-turnPolarToY(1,1:360)Z1<-rep(0,360)...
2011 Jun 07
2
gam() (in mgcv) with multiple interactions
...ather be able to stay with just the two-way (and one three-way) interactions that I know are of interest (I know this from previous logistic regression modelling of the dataset).
For those who like to see the actual R code, here are two fits I've tried:
gam(outcome ~ te(acl, dispersal) + te(amplitude, dispersal) + te(slope, curvature, amplitude), family=binomial, data=rla, method="REML")
gam(outcome ~ te(slope) + te(curvature) + te(amplitude) + te(acl) + te(dispersal) + te(slope, curvature) + te(slope, amplitude) + te(curvature, amplitude) + te(acl, dispersal) + te(amplitude, dispers...
2009 Aug 10
1
manipulating text to generate different formulas to use in nls()
...ue7, f2=some.value8, f3=some.value9 )
So far, I managed to create the "building blocks" I need but when it comes to defining their
number I still haven't found a solution (see the following code).
## some fake starting values
par.ini <- data.frame(period=1:5, invR=1:5, a0=1:5, Amplitude=1:5, Phase=1:5)
n <- nrow(par.ini) - 1 # I'm not interested in the last harmonic
inip <- par.ini[1:n, c(1, 3:5)] # neither in the second column
amps <- paste("A", 1:n, sep="")
phas <- paste("P", 1:n, sep=&...
2017 Jun 25
0
Writing my 3D plot function
...plicity) but
>unfortunately I have the cartesian coordinates legends that do not help
>on reading my Figure. You can help me by executing the code below?
>
>require("rgls")
>degreeToRadian<-function(degree){? return ? (0.01745329252*degree)}
>turnPolarToX<-function(Amplitude,Coordinate){? return
>(Amplitude*cos(degreeToRadian(Coordinate)))}
>turnPolarToY<-function(Amplitude,Coordinate){? return
>(Amplitude*sin(degreeToRadian(Coordinate)))}
># Putting the first circle on 3d space. Circle of radius
>1X1<-turnPolarToX(1,1:360)Y1<-turnPolarToY(1,1:3...
2017 Jun 21
2
fitting cosine curve
What I did was to plot your initial values, then plot the smoothed
values and guess the constants. That is, I got an "eyeball" fit to the
smoothed values. As I have described this as "gross cheating" in the
past, you should either split your data, estimate on one subset and
then test on another, or estimate on your data and test on a
replication. If you get pretty much the same
2005 Dec 12
2
mdf -- better adaption of W?
...rge an ammount of the original signal at time offset j the
>> echo canceller thinks should be removed from the current input frame.
>
> Careful when looking at W because of how the real and imaginary parts
> are packed in the array.
Err. Ok, as I got it, 'bin 0' has it's amplitude in W[0], bin 1 to N-1 has
it's real part in W[i*2-1] and it's imag in W[i*2], and finally the
nyquist amplitude is in W[N-1]
I took this from how power_spectrum() computes, so I might be off :)
>> Anyway, I did some proper testing. I took my headset, bent the microphone
>> a...
2008 Jan 23
1
help with levelplot()
useR's,
I want to create a "movie" of a sin function (from 0 to pi/2) using
levelplot() in the lattice package. I basically want to create 20 or so
plots of the sin function starting with an amplitude of 0 and ending at
amplitude 1. By using a loop and plotting these in succession, it will have
the appearance of a movie or animation. I believe I know how to do this
part, but I am having trouble working with the colors.
I want to use a range of colors starting with light blue (denoting zero) an...
2011 Feb 13
1
calculate phase/amplitude of fourier transform function in R
...retization interval $w = [-\pi:.1*\pi: \pi]$?
Then, how do I find the 'magnitude' of spectrum and 'phase' of spectrum in
R?
Is there an existing package/function in R? An example would be very
helpful.
--
View this message in context: http://r.789695.n4.nabble.com/calculate-phase-amplitude-of-fourier-transform-function-in-R-tp3303345p3303345.html
Sent from the R help mailing list archive at Nabble.com.
2007 Jul 09
1
a way restrict encoding sound volume
You have the point.
"I get very distorted speech when using libspeex in my application. What¡¯s
wrong?
....
If the input speech has an amplitude close to ¡¾2^15, it is possible that
at decoding, the amplitude be a bit higher than that, causing clipping when
saving as 16-bit PCM."
This is one of FAQs in 'speex-manual' you wrote. I guess amplitudes close
to 2^15 bother me. Do you have any idea to avoid it? I believe speex giv...
2005 Apr 16
1
How to get predictions, plots, etc. from lmer{lme4}
Kindly send a cc to me when replying to the list.
I'm having trouble using lmer beyond a first step.
My data:
> some(exp1B)
sub ba amplitude a b c d
2 1 1.00 1.5 65 63 4 8
41 4 1.15 0.0 92 41 3 4
43 4 1.15 3.0 88 48 2 2
63 6 1.00 3.0 50 72 9 9
77 8 1.15 0.0 112 25 2 1
89 10 1.15 0.0 37 33 36 34
126 13 1.15 1.5 80 50 6 4
140 14 1.15 4.5 12...
2008 Jun 10
3
fitting periodic 'sine wave' model
I have been attempting to estimate the periodic contribution of an
effect to some data but have not been able to fit a sine wave within R.
It would be nice to start by being able to fit a sine wave with an
amplitude and frequency.
x<-seq(0,20,by=0.5)
y<-2*sin(2*pi*.5*x) #amplitude =2, frequency=0.5
# This failed to converge
r<-nls(y ~ A*sin(2*pi*F*x), start=list(A = 1, F = 1), trace=T)
# even this gave a max iteration error
r<-nls(y ~ A*sin(2*pi*F*x), start=list(A = 1, F = .5), trace=T)
I have...