similar to: Numerical integration problem

Displaying 20 results from an estimated 6000 matches similar to: "Numerical integration problem"

2009 Aug 06
2
Convert dataframe to table with counts where column names become row names
Can anyone explain how best to go from a dataframe to a table (or better yet a new dataframe) of counts, where the row names in the new table (or dataframe) are the column names of the original df. start w/ DF1 = Pos1 Pos2 Pos3 .... oligo1 G C A oligo2 U U A oligo3 G C C oligo4 C G U oligo5 A A G ..... End with DF2 =
2001 Nov 29
2
plotting (a) confidence intervals (b) standard error
Hi all, I'm building a plot of the values in tmeant (below) against positions 1 to 5, using matplot. tmeant looks like this: case1 case2 pos1 861.8466 818.5909 pos2 961.2841 976.3466 pos3 878.6080 1262.8523 pos4 950.8011 1129.6080 pos5 968.1080 1063.3920 I also have lower (object tl) and upper (object tu) bounds on the confidence intervals as follows: tl: pos1
2010 May 04
1
Avoiding for-loop for splitting vector into subvectors based on positions
Dear all, I'm trying to optimize code and want to avoid for-loops as much as possible. I'm applying a calculation on subvectors from a big one, and I get the subvectors by using a vector of starting positions: x <- 1:10 pos <- c(1,4,7) n <- length(x) I try to do something like this : pos2 <- c(pos, n+1) out <- c() for(i in 1:n){ tmp <- x[pos2[i]:pos2[i+1]]
2007 Jan 19
3
integrate and quadratic forms
Hi all. I'm trying to numerically invert the characteristic function of a quadratic form following Imhof's (1961, Biometrika 48) procedure. The parameters are: lambda=c(.6,.3,.1) h=c(2,2,2) sigma=c(0,0,0) q=3 I've implemented Imhof's procedure two ways that, for me, should give the same answer: #more legible integral1 = function(u) {
2010 Jul 06
1
plotmath vector problem; full program enclosed
Here's another example of my plotmath whipping boy, the Normal distribution. A colleague asks for a Normal plotted above a series of axes that represent various other distributions (T, etc). I want to use vectors of equations in plotmath to do this, but have run into trouble. Now I've isolated the problem down to a relatively small piece of working example code (below). If you would
2005 May 16
1
branch cuts of atan()
Hi the following gave me a shock: > atan(2) [1] 1.107149 > atan(2+0i) [1] -0.4636476+0i > or, perhaps more of a gotcha: > atan(1.0001+0i) [1] -0.7853482+0i > atan(0.9999+0i) [1] 0.7853482+0i > evidently atan()'s branch cuts aren't where I thought they were. Where do I look for documentation on this? -- Robin Hankin Uncertainty Analyst National
2004 Dec 16
3
Qyery on bark equation in floor0 code
Hi All, I need some clarifications regarding the mismatch I found in the code and the specification. (a) In the specification, the bark(x) equation is given as: bark(x) = 13.1 atan(.00074x) + 2.24 atan(.0000000158(x^2)) + .0001x whereas in the code it is given as: #define toBARK(n) (13.1f*atan(.00074f*(n))+2.24f*atan((n)*(n)*1.85e-8f)+1e-4f*(n)) Which one of these is the proper one ? (b)
2001 Aug 12
3
gam() and library( modreg )
Hi, I'm just wonder if there is an R equivalent function of gam() - which exist in Splus. Also does anyone know if the library( modreg ), which comes with the installation file of R 1.3.0 (Windows version), exists in the previous versions of R (again, Windows version)? Or does one need to install the library into the previous versions of R explicitly? Thanks, Ko-Kang Wang
2000 Nov 26
2
References for the BARK/MEL stuff
Could someone point me to the BARK/MEL tables that these macros (from vorbis/scales.h) are trying to approximate? #define toBARK(f) (13.1*atan(.00074*(f))+2.24*atan((f)*(f)*1.85e-8)+1e-4*(f)) #define fromBARK(z) (102.*(z)-2.*pow(z,2.)+.4*pow(z,3)+pow(1.46,z)-1.) #define toMEL(f) (log(1.+(f)*.001)*1442.695) #define fromMEL(m) (1000.*exp((m)/1442.695)-1000.) I was wondering if I could come
2006 Mar 28
2
atan2(1,1i)
Hi ?atan2 says that atan2(y,x)=atan(y/x) for x and y numeric or complex vectors. Well, I would expect atan2(1,1i) to be equal to atan(-1i), but > atan2(1,1i) Error in atan2(y, x) : Non-numeric argument to mathematical function > R.version _ platform powerpc-apple-darwin8.5.0 arch powerpc os darwin8.5.0 system powerpc, darwin8.5.0
2006 Mar 28
2
atan2(1,1i)
Hi ?atan2 says that atan2(y,x)=atan(y/x) for x and y numeric or complex vectors. Well, I would expect atan2(1,1i) to be equal to atan(-1i), but > atan2(1,1i) Error in atan2(y, x) : Non-numeric argument to mathematical function > R.version _ platform powerpc-apple-darwin8.5.0 arch powerpc os darwin8.5.0 system powerpc, darwin8.5.0
2004 Jan 21
2
derivative of atan(x) and similar functions
Dear R experts. 'D()' function recognizes some of the analitical functions, such as sin, cos, etc. But I'd like to take analytical derivatives from asin, atan etc. functions. Are there any R packages providing that features? Thanks. -- Timur.
2006 Apr 04
2
ogg + theora + seeking
Hi all, I'm actually learning how to use ogg, theora and vorbis. My idea is to create a small program running, that is able to concatenate ogg video+audio files. However I have some small questions. Here I will start with the first one: I read the following for seeking in ogg for a theora key-frame: ---- snipp (http://www.xiph.org/ogg/doc/ogg-multiplex.html) ---- [...]The third point
2005 Apr 14
1
Strange behavior of atan2
Dear all, I've got a problem with the function atan2. For a couple of coordinates x and y, This function returns the angle between the vector of coordinates (x, y) and the abscissa axis, i.e. it is the same as atan(y/x) (as indicated on the help page). If we consider the vector with coordinates x = 0 and y = 0, we have the following result: > atan(0/0) [1] NaN This is expected.
2005 Aug 17
1
GLM/GAM and unobserved heterogeneity
Hello, I'm interested in correcting for and measuring unobserved heterogeneity ("missing variables") using R. In particular, I'm searching for a simple way to measure the amount of unobserved heterogeneity remaining in a series of increasingly complex models (adding additional variables to each new model) on the same data. I have a static database of 400,000 or
2014 Mar 20
2
BARK implementation (or specification) error
Hi, In the course of some work which I describe below, I have found a very significant difference between the BARK function described in the Vorbis specification and its implementation in libvorbis. In the specificationhttp://xiph.org/vorbis/doc/Vorbis_I_spec.pdf bark(x) = 13.1arctan(.00074x) + 2.24arctan(.0000000185x**2 + .0001x) In the libvorbis code
2004 Apr 11
3
pcauchy precision (PR#6756)
Full_Name: Morten Welinder Version: snapshot OS: Submission from: (NULL) (65.213.85.129) Two things are wrong. 1. There is nan test outside IEEE_754. 2. The meat part of the function should really be something like... if (!lower_tail) x = -x; if (fabs (x) > 1) { double temp = atan (1 / x) / M_PI; return (x > 0) ? R_D_Clog (temp) : R_D_val (-temp); } else
2008 Feb 06
2
kinship package: drawing pedigree error
Hi Im using the kinship package to draw a pedigree. On my data set this works fine but when i add indivudals to the pedigree i keep getting an error i hope someone can help me! This is the code im using: Data<-read.table("Tree.txt", header=T, sep=",") attach(Data) ped<-pedigree(id, dadid, momid, sex, aff) par(xpd=T) plot.pedigree(ped) This is my data looks like
2009 Aug 27
2
setting par(srt) according to plot aspect ratio
How can I look up the aspect ratio of a plot, so I can use that to correctly adjust the angle of text which is supposed to be parallel to a line in the plot? The following example code works for a 1:1 aspect ratio, but puts the text at the wrong angle if the plot region is short and wide or tall and narrow. I can't find a par() component containing the plot aspect ratio. It will be for
2008 May 27
5
Rotated text on a regression line
Dear all, I stumbled over a problem recently when trying to use srt with text() on a windows device. What I intended to do was to plot a simple regression line, and to rotate a piece of text such that the text has the same angle as the regression line. However, the text is always plotted in a slightly wrong angle: #### x=1:10 #create arbitrary x and y values y=x*2-rnorm(1:10)