similar to: piecewise linear approximation

Displaying 20 results from an estimated 1000 matches similar to: "piecewise linear approximation"

2006 Aug 07
1
Running out of memory when using lapply
Hi all! I'm afraid I programmed something totally non-sensical and inefficient, but I can't figure out how to do it better. I have a list of ~ 40 000 characters. I want to take each element at a time, map it to a large data frame with hit=which(data.frame$column==elementFromList), then compute some statistic on data.frame[hit,] and return a result that consists of either 1) a list
2011 Nov 01
2
drawing ellipses in R
Hello, I have been following the thread dated Monday, October 9, 2006 when Kamila Naxerova asked a question about plotting elliptical shapes. Can you explain the equations for X and Y. I believe they used the parametric form of x and y (x=r cos(theta), y=r sin(theta). I don't know what r is here ? Can you explain 1)the origin of these equations and 2) what is r? Sincerely, Mary A. Marion
2006 Oct 09
2
Add ellipse to plot
Is there a way to plot elliptical shapes? symbols() only provides circles... Thanks! Kamila
2006 Apr 18
1
Different results under Windows and Linux
Hi everyone, disturbingly, a PCA yields different results when I run the analysis under Windows and Linux. I open the same workspace (which is on an independent partition) and perform the exact same function (by using the history file). Interestingly, PC1 is the same, but PC2 comes out totally different. Thanks! Kamila Windows: platform i386-pc-mingw32 arch i386 os
2006 Sep 15
1
plot region too large
Hi! I don't understand this: layout(matrix(c(1:10),5,2),heights=c(1,rep(2,4))) plot(1,1) error in plot.new() : plot region too large Why?????? Thanks! Kamila
2007 Nov 08
1
Installing the Matrix package
Hi all, is the Matrix package no longer available for download via install.packages? When I try to install it (from any mirror), I get the following error message: install.packages("Matrix",lib="/home/kn52/R-2.5.0/library") Warning message: package 'Matrix' is not available in install.packages("Matrix",lib="/home/kn52/R-2.5.0/library") Other
2005 Jan 12
4
Finding seasonal peaks in a time series....
I have a seasonal time series. I want to calculate the annual mean value of the time series at its peak (say the mean of the three values before the peak, the peak, and the three values after the peak). The peak of the time series might change cycle slightly from year to year. # E.g., nPts <- 254 foo <- sin((2 * pi * 1/24) * 1:nPts) foo <- foo + rnorm(nPts, 0, 0.05) bar <- ts(foo,
2005 May 30
3
Piecewise Linear Regression
Hi, I need to fit a piecewise linear regression. x = c(6.25,6.25,12.50,12.50,18.75,25.00,25.00,25.00,31.25,31.25,37.50,37.50,50.00,50.00,62.50,62.50,75.00,75.00,75.00,100.00,100.00) y = c(0.328,0.395,0.321,0.239,0.282,0.230,0.273,0.347,0.211,0.210,0.259,0.186,0.301,0.270,0.252,0.247,0.277,0.229,0.225,0.168,0.202) there are two change points. so the fitted curve should look like \ \ /\
2013 Jan 26
2
confidence / prediction ellipse
Hi, I'm using the R library(car) to draw confidence/prediction ellipses in a scatterplot. >From what i understood the ellipse() function return an ellipse based parameters: shape, center, radius . If i read dataEllipse() function i can see how these parameters are calculated for a confidence ellipse. ibrary(car) a=c(12,12,4,5,63,63,23) b=c(13,15,7,10,73,83,43) v <-
2010 Oct 11
1
MATLAB vrs. R
I need to find the area under a trapezoid for a research-related project. I was able to find the area under the trapezoid in MATLAB using the code: function [int] = myquadrature(f,a,b) % user-defined quadrature function % integrate data f from x=a to x=b assuming f is equally spaced over the interval % use type % determine number of data points npts = prod(size(f)); nint = npts -1; %number of
2005 Jun 25
2
optimization problem in R ... can this be done?
Im trying to ascertain whether or not the facilities of R are sufficient for solving an optimization problem I've come accross. Because of my limited experience with R, I would greatly appreciate some feedback from more frequent users. The problem can be delineated as such: A utility function, we shall call g is a function of x, n ... g(x,n). g has the properties: n > 0, x lies on the
2007 May 07
1
Simple question about function with glm
Dear all, I coded a function called u.glm u.glm <- function (x,ahi,age,bmiz,gender) { library(nortest) lil.rslt <- lillie.test(x) if (lil.rslt$p.value >0.05) { cat("Logtrans=0, lillie=",lil.rslt$p.value,"\n") xmodel<-glm(x~ahi+age+bmiz+as.factor(gender)) summary(xmodel) confint(xmodel) } else { cat("Logtrans=1,
2006 Jan 08
1
confint/nls
I have found some "issues" (bugs?) with nls confidence intervals ... some with the relatively new "port" algorithm, others more general (but possibly in the "well, don't do that" category). I have corresponded some with Prof. Ripley about them, but I thought I would just report how far I've gotten in case anyone else has thoughts. (I'm finding the code
2001 Feb 28
2
Automating the job?
Hi! I just started to use R recently, and would like to ask a help about automating the job. I need to use "kmeans" function with my own 300 data files, and wonder if it's possible to do it automatically. For example, > library (mva) > mydata <- read.table ("data1") > cl <- kmeans(mydata, 5, 20) and I just need to save "cl" info (i.e. the center
2003 Mar 26
3
hist overlay...
thanks to all for the 2d scatter plot. i have one more. how do i plot 'hist(y1, col="red") and hist(y2,col="blue") in the same window? thanks again.
2015 Dec 28
1
[PATCH 2] more changes in bitmath.h
1) FLAC supports only MSVS 2005 and newer, so (_MSC_VER >= 1400) is always true and can be removed. 2) The argument for FLAC__clz_uint32() is of FLAC__uint32 type, so FLAC__clz_soft_uint32() should have the same argument type. 3) The patch removes unnecessary parentheses around 'word' variable. 4) It also replaces "sizeof(FLAC__uint32) * CHAR_BIT - 1 -
2006 Oct 05
1
unexpected behavior of boxplot(x, notch=TRUE, log="y")
A function I've been using for a while returned a surprising [to me, given the data] error recently: Error in plot.window(xlim, ylim, log, asp, ...) : Logarithmic axis must have positive limits After some digging I realized what was going on: x <- c(10460.97, 10808.67, 29499.98, 1, 35818.62, 48535.59, 1, 1, 42512.1, 1627.39, 1, 7571.06, 21479.69, 25, 1, 16143.85, 12736.96,
2006 Jan 23
1
too-large notches in boxplot (PR #7690)
PR #7690 points out that if the confidence intervals (+/-1.58 IQR/sqrt(n)) in a boxplot with notch=TRUE are larger than the hinges -- which is most likely to happen for small n and asymmetric distributions -- the resulting plot is ugly, e.g.: set.seed(1001) npts <- 5 X <- rnorm(2*npts,rep(3:4,each=npts),sd=1) f <- factor(rep(1:2,each=npts)) boxplot(X~f) boxplot(X~f,notch=TRUE) I can
2007 Nov 07
1
strwidth and strheight for rotated text
Dear All, I would like to plot text with a box around it. I used strwidth and strheight to compute the size of the box which is plotted with rect: z <- rnorm(10) # horizontal text works plot(rnorm(10)) x1 <- 5 y1 <- 0 label <- "Label" cha <- paste(" ", label, " ", sep = "") xh <- strwidth(cha, cex = par("cex")) yh <-
2006 Jan 19
1
nls profiling with algorithm="port" may violate bounds (PR#8508)
[posted to R-devel, no discussion: resubmitting it as a bug, just so it gets logged appropriately] Sorry to report further difficulties with nls and profiling and constraints ... the problem this time (which I didn't check for in my last round of testing) is that the nls profiler doesn't seem to respect constraints that have been set when using the port algorithm. See test code