similar to: Chromatogram deconvolution and peak matching

Displaying 20 results from an estimated 130 matches similar to: "Chromatogram deconvolution and peak matching"

2007 Dec 06
2
Any package for deconvolution?
I want to run deconvolution of a time series by an impulse or point-spread function through Wiener filter, regularized filter, Lucy-Richardson method, or any other approaches. I searched the CRAN website and the mailing list archive, but could not find any package for such a deconvolution analysis. Does anybody know an existing R function for deconvolution? TIA, Gang
2008 Feb 23
1
Bimodal deconvolution
Hi Everyone- After searching through posts and my favorite R-help websites I'm still confused about a problem. I have data which is bimodal in nature, but there is no clearly obvious separation between the two peaks. In programs such as Origin, I can deconvolute the two distributions and have it generate a "best guess" as to what the two subpopulations are which make up my
2007 Mar 09
2
Deconvolution of a spectrum
Dear useRs, I have a curve which is a mixture of Gaussian curves (for example UV emission or absorption spectrum). Do you have any suggestions how to implement searching for optimal set of Gaussian peaks to fit the curve? I know that it is very complex problem, but maybe it is a possibility to do it? First supposement is to use a nls() with very large functions, and compare AIC value, but it is
2018 May 31
2
How to alpha entire plot?
I have two chromatograms I want plotted on the same axes. I would like the plots to be transparent, so the first chart is not obscured. I have tried adjustcolor(..., alpha.f=0.3), the problem is that my chromatogram is so dense with datapoints that they overlap and the entire graph just ends up a solid color. The second histogram still obscures the first. Consider this example: col1 <-
2013 Mar 18
2
OrgMassSpecR peak area issue
Hello! I am having an issue with the OrgMassSpecR package. I run my HPLC using a DAD detector. My raw data is exported form chemstation as a csv file. I then upload the csv into Rstudio no problem. Using the DrawChromatogram function, I get a nice chromatogram, and my retention time, peak area, and apex intensity values are given as well. The problem comes with the peak area value given. The
2011 Feb 18
1
Find peaks in dataset(x,y) and area for each peak
http://r.789695.n4.nabble.com/file/n3312061/x_and_y_values.txt x_and_y_values.txt I have the absorbance values form HPLC Chromatogram. I need to find the peaks in datapoints and area under each peak. I am not sure how how to find the peaks, I tried couple of libraries and peak function but they return me a list of values which when computed from area turns out to be huge nnumbers. In the
2009 Feb 22
3
Error in var(x, na.rm = na.rm) : no complete element pairs
Hello all, I'm trying to calculate the standar desviation and I'm using the function sd(x,na.rm=TRUE) and I have this error:? Error in var(x, na.rm = na.rm) : no complete element pairs . Why happen this?, What can I do to solve it?. x is list of three numbers which I have from a table. Thanks so much from Spain Carlos Morales Diego
2008 Feb 04
1
Concatenation and Evaluation
Hello all, I've run into what I bet is a silly problem; however, I've been trying to get around it now for a couple weeks and every time I think I have the answer it still doesn't work. So I apologize in advance if this is painfully obvious, but I've run out of ideas and would really appreciate any input. My situation is this, I'm importing a number of tab
2006 Jul 11
3
least square fit with non-negativity constraints for absorption spectra fitting
I would really appreciate it if someone can give suggestions on how to do spectra fitting in R using ordinary least square fitting and non-negativity constraints. The lm() function works well for ordinary least square fitting, but how to specify non-negativity constraints? It wouldn't make sense if the fitting coefficients coming out as negative in absorption spectra deconvolution. Thanks.
2011 Nov 15
3
Question about linear regression in R
Hi all, I wrote a r program as below: x <- 1:10 y <- c(3,3,3,3,3,3,3,3,3,3) fit <- lm(log(y) ~ x) summary(fit) And I expect to get some error message from R, because "y" is constant. But, I got the message as below: > summary(fit) Call: lm(formula = log(y) ~ x) Residuals: Min 1Q Median 3Q Max -6.802e-17 -3.933e-17 -1.063e-17 1.807e-17
2008 Oct 30
1
Formula for Xi
Hallo! <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p> <o:p> </o:p> I want to compare different samples with the formula … <o:p></o:p> <o:p> </o:p> Here some example data: <o:p></o:p> <o:p> </o:p> <o:p> </o:p> sample1<o:p></o:p>
2003 Oct 08
1
using split.screen() in Sweave
Dear R and sweave users A further problem, which I couldn't resolve, using the manual: In R I use the split.screen command to put e.g. two timecourses one above the other into one plot: split.screen(c(2,1)) screen(1) plot(stick,type='h', col="red",lwd=2) screen(2) plot(deconvolution.amplitude,type='h',col="blue",lwd=2) Is there a similar way, doing this
2008 Mar 26
1
deconv
I'm translating a matlab routine to R and I need some equivalent to deconv(): Description: deconv() [q,r] = deconv(v,u) deconvolves vector u out of vector v, using long division. The quotient is returned in vector q and the remainder in vector r such that v = conv(u,q)+r . If u and v are vectors of polynomial coefficients, convolving them is equivalent to multiplying the two polynomials, and
2018 Jun 01
0
How to alpha entire plot?
Interesting problem. I would discretize the x-values and interleave them. Lines from one dataset still overlap, so you see high- density and low-density regions, but lines from the other dataset are drawn into the interval. Like so: interleave <- function(x, MIN, MAX, N, nChannel = 2, channel) { isp <- seq(MIN, MAX, length.out = N + 1) # interleave support points offset <-
2011 Aug 08
1
msProcess, creating msSet file(s)
I have 120 MS chromatograms containing two columns'Time' and 'Peak height'. how do in create a msSet file which is required by all the functions of 'msProcess' to process these files. I would appreciate help very much. Thanks Sharad -- View this message in context: http://r.789695.n4.nabble.com/msProcess-creating-msSet-file-s-tp3727959p3727959.html Sent from the R help
2007 Feb 20
1
baseline fitters
I am pretty pleased with baselines I fit to chromatograms using the runquantile() function in caTools(v1.6) when its probs parameter is set to 0.2 and its k parameter to ~1/20th of n (e.g., k ~ 225 for n ~ 4500, where n is time series length). This ignores occasional low- side outliers, and, after baseline subtraction, I can re-adjust any negative values to zero. But runquantile's
2006 Jan 05
4
Q: R 2.2.1: Memory Management Issues?
Dear Developers: I have a question about memory management in R 2.2.1 and am wondering if you would be kind enough to help me understand what is going on. (It has been a few years since I have done software development on Windows, so I apologize in advance if these are easy questions.) ------------- MY SYSTEM ------------- I am currently using R (version 2.2.1) on a PC running Windows 2000
2008 Jul 21
5
Coefficients of Logistic Regression from bootstrap - how to get them?
Hello all, I am trying to optimize my logistic regression model by using bootstrap. I was previously using SAS for this kind of tasks, but I am now switching to R. My data frame consists of 5 columns and has 109 rows. Each row is a single record composed of the following values: Subject_name, numeric1, numeric2, numeric3 and outcome (yes or no). All three numerics are used to predict
2006 Jul 19
3
Fitting a distribution to peaks in histogram
Hello list! I would like to fit a distribution to each of the peaks in a histogram, such as this: http://photos1.blogger.com/blogger/7029/2724/1600/DU145-Bax3-Bcl-xL.png . The peaks are identified using Petr Pikal peaks function ( http://finzi.psych.upenn.edu/R/Rhelp02a/archive/33097.html), but after that I am quite stuck. Any idea as to how I can: Fit a distribution to each peak Integrate the
2012 Jun 21
2
Simple Question?
Greetings, I am new to R, but trying to put in the time to learn. I have read the R manual and several other introductory texts; however, there is nothing like actually putting it into practice. So here is my problem, and its more of a learning exercise for myself than anything else, but I'm stuck and getting extremely frustrated that I can't figure it out. I'm trying to make a