similar to: Applying a function of several variables to data

Displaying 20 results from an estimated 4000 matches similar to: "Applying a function of several variables to data"

2000 Aug 04
1
Inverting matrix...
Dear all, Either I'm being totally blind now (as you know, the eyes are the first thing that is blinded :-)), or something is missing in "An Introduction to R". The section heading of section 5.7.1 is "Multiplication, inversion and solving linear equations", and since I was looking for the canonical way of inverting a matrix, this was the place to look. However, I found
2001 Jun 04
1
2D convolution
Dear all, I have an image that I need to filter, and so I'm looking for a method to convolve it with a matrix. If I understood the docs for convolve correctly, it only works in 1D (and I have tried to convolve, it didn't look good). So, I wondered if anybody have implemented 2D convolution in R, or have any good advices to share (beyond having a look at mvfft), before I go hacking?
2000 Feb 13
1
Underflow warnings?
Dear all, I'm a bit concerned about underflow problems. Such problems typically occur when two almost equal numbers are subtracted. I was wondering if R has any mechanisms for warning users about potential problems, or if any policy has been developed? To check, I just did: > 1.0000000000000001 - 1 [1] 0 > 1.000000000000001 - 1 [1] 1.110223e-15 > 1.00000000000001 - 1 [1]
2001 Apr 30
1
Some loglog density plot
Dear all, A looong time ago, Witold Eryk Wolski asked here why there wasn't a log="xy" parameter to the hist() function <URL:http://www.R-project.org/nocvs/mail/r-help/2001/0267.html>, and Prof. Ripley responded that a loglog histogram does not make much sense, and that one should use a better density estimate if one seeks to plot log density. I understand the point and I
2000 Nov 08
1
Re: [R] Strange means of numbers drawn from rpois (PR#730)
On 8 Nov 2000, Peter Dalgaard BSA wrote: >Done... Great! >(This kind of behaviour has been observed on various platforms and >various compilers, sometimes getting stuck around 15.15 and sometimes >around 14.5. Others report no problems. Very strange. I've seen one >case where it apparently shifted from one regime to the other.) Yes, it does that here too.... The following is
2001 Nov 16
1
$name vs. [["name"]]
Dear all, I have been away for a month, but some time ago, I noted something that was very surprising to me. I think this example illustrates it well: > test <- data.frame(col1 = c(1,2), col2=c(3, 4)) > test col1 col2 1 1 3 2 2 4 > apply(test, 1, function(x) browser()) Called from: FUN(newX[, i], ...) Browse[1]> x$col1 NULL Browse[1]> x[["col1"]] [1] 1
2000 Apr 27
0
What is ks.test saying?
Hello! I have two matrices of equal dimension ll and lu that I want to do a ks.test on corresponding rows in these matrices (dim(ll) is [1] 101 100). If I do e.g. > ks.test(ll[50,],lu[50,]) just for testing, it displays a lot of numbers, and some more info: [116] -3.000000e-02 -4.000000e-02 -4.000000e-02 -3.000000e-02 -4.000000e-02 [121] -3.000000e-02 -4.000000e-02 -3.000000e-02 -2.000000e-02
2000 Dec 07
1
Reversing x-axis
Dear all, I'm making a system to create a star-chart, and I have encountered one of the intuitive and clearly thoughtful conventions that are so common in astronomy :-J... Well, the point being, I have to reverse the x-axis. I figured, I might just set xlim=rev(range(x)). Do e.g. > x <- 0:5 > y <- (0:5)^3 > plot(x, y) > plot(x, y, xlim=rev(range(x))) The problem is that here
2000 Jun 27
0
Unimplemented feature in copyVector
Dear all, I started a large run this afternoon, and when I came back after dinner, three of five processes had stopped with the error message: Error in matrix(nullprofile, length(nullprofile), nprofiles) : Unimplemented feature in copyVector I have seen anything about this anywhere (and I don't know where to look...). As you might guess, I'm trying to make a matrix where the
2000 Jul 27
1
Interpolation using a piecewise linear function in higher dimensions
Dear all, I am just wondering if anybody has implemented a function that can give a piecewise linear interpolation in more than 2 dimensions? I have looked at the akima package, but I would rather like a piecewise linear interpolation rather than a spline and while it did the job quite satisfactory for 2 dimensions, I need to interpolate in at least three dimensions. If anybody has implemented
2000 Jan 14
2
Matrix output from drawing functions
Dear all, I'm a bit confused about the output from functions that generates random values, e.g. rpois. I'm using 0.65.1 on Digital UNIX alphaev6. If I say > rpois(10,5) output is not unexpectedly: [1] 4 6 5 7 6 5 2 2 5 3 but I figured that if I go: > rpois(10,1:10) I would get a 10x10 matrix as output, with random values for each of the vector elements in the row vectors, but
2000 Jun 24
1
Garbage Collecting
Dear all, Me and the Garbage Collector doesn't understand each other... I'm on R-1.0.1 (I have requested an upgrade to the right local people), an osf1 system with an alphaev6 CPU. I have fair amounts of memory to use, but it seems to be used up pretty fast nevertheless. I'm now trying to see what the garbage collector does, I have inserted a gc(v=T) call at a spot in my code. I
2000 Jun 09
0
Disappearing values (PR#551)
Dear all, Uwe e-mailed me yesterday about the problems some time ago. I had hoped someone would have a look at our computers, but due to some unfortunate circumstances, it hasn't happened. However, it seems unlikely that it is connected to a specific piece of hardware. It could be an architecture-dependent problem though. I also had a word with those who did the installation of R, and they
2001 Aug 08
1
Strategy for creating a palette...?
Dear all, I'm generally not a big fan of GUIs, but I have just discovered one thing where a GUI would be a nice thing: creating color palettes. I'm creating an "image", for transparencies for a lecture I'm giving, so this is going to look great... :-) What I'm out for, is to make green tones and red tones, and a relatively sharp break between them. This break will
2000 May 12
1
Geometric Distribution at prob=c(0,1)
Dear all, I''m working with the geometric distribution for the time being, and I''m confused. This may have more to do with statistics than R itself, but since I''m getting results from R I find counterintuitive (well, yeah, my statistical intuition has not been properly sharpened), I feel like asking. The point first: If I do > rgeom(1,prob=1) I get: [1] NaN Warning
2002 Feb 18
0
Kudos (and SVG)
Dear all, I have just finished my thesis titled "Gravitational Microlensing of Quasar Clouds", and the following paragraph appeared in my "Acknowledgements": "I would like to thank the authors of R and the R core team for their great skill and dedication in developing this software, and to all the members of the R-help mailing list, especially Brian D. Ripley,
2001 Aug 02
1
Package GSS for interpolation in more than 2D?
Dear all, There has been some time since I asked about interpolation in higher (>2) dimensions, and I must admit I failed to write a function to do this myself the last time, but eventually ended up doing it in MATLAB. I tried to translate the MATLAB code, but MATLAB code is so much more opaque than R (S) code, so I failed that too, mainly because I could only get one MATLAB session, I would
2002 Jan 10
0
Add qqline to plot.lm Q-Q plot?
Dear all, Is there a simple way to add a qqline to the Q-Q plot plot.lm() produces for which = 2? If not, I might write one, but how should this preferably be implemented? Make qqline() generic and add a qqline.lm() method? Add an argument to plot.lm()? Have plot.lm() output something invisibly that qqline() can chew directly? Have plot.lm() output something invisibly that abline() can chew?
2000 Mar 23
1
Some "new" stuff for hist.R
This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. Send mail to mime@docserver.cac.washington.edu for more info. --0-201145637-953833073=:7710 Content-Type: TEXT/PLAIN; charset=US-ASCII Dear all, I've been hacking on histograms the past couple of days. I wanted to do two things, add
2000 Apr 04
0
Obscure bug....?
Dear all, I've been struggling for days now with a piece of code that I have posted here before, that has a really obscure bug. I think I may have isolated it, but I have no idea what it is.... It might also be a bug in R I guess, as it seems that one or several of list elements are not passed when a function is called, but quite rarely. I have been hacking rather wildly on the histogram