similar to: strip function

Displaying 20 results from an estimated 2000 matches similar to: "strip function"

2008 Feb 12
3
regular expression for na.strings / read.table
Dear all, I am working with a csv file. Some data of the file are not valid and they are marked with a star '*'. For example : *789. I have attached with this email a example file (test.txt) that looks like the data I have to work with. I see 2 possibilities ..thast I cannot manage anyway in R: 1-first & easiest solution: Read the data with read.csv in R, and define as na strings
2007 May 24
6
Sum per hour
Dear all, I have a list of precipitation record and a list of time I would like to sum them up per hour, or per day. Does such a function exist ? example: time<-c("2000-10-03 14:00:00","2000-10-03 14:10:00","2000-10-03 14:20:00","2000-10-03 15:30:00","2000-10-03 16:40:00","2000-10-03 16:50:00","2000-10-03
2007 May 08
3
plot time series
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2006 Sep 27
1
exponential fitting
Hi, I would like to fit some experimental points by a exponential function. I ignore the parameters of this exponential and what I would like is to ask R to calculate the best fitting curve an the associated parameters (as the linear model function (lm) does for linear models). Is it possible ? Do anyone have an idea about how to do that ? Thanks by advance Jessica Gervais [[alternative
2006 Sep 27
1
panel.curve
Hi, I am trying to fit experimental points by exponemtial curve my data are stored into a matrix data the first column is the geographical point (a number = data[,1] ) ( I would like to plot several graphes at the same time) the second column is the time of measurement (x in the plot) the third column is a speed (y in the plot) if we assume the point are folowing this exponential behaviour
2006 Oct 19
1
extract arguments from a list
Hi, I would like to know how to extract the arguments from a list : For example, I have a list of charchacter x x<- c("Bentazone","Atrazine","Epoxiconazol","Metolachlor","Epoxiconazol","Atrazine desethyl","Fenpropimorph","Epoxiconazol","Metolachlor","Simazine","Atrazine
2009 Aug 24
2
robust method to obtain a correlation coeff?
Hi, Being a R-newbie I am wondering how to calculate a correlation coefficient (preferably with an associated p-value) for data like: > d[,1] [1] 25.5 25.3 25.1 NA 23.3 21.5 23.8 23.2 24.2 22.7 27.6 24.2 ... > d[,2] [1] 0.0 11.1 0.0 NA 0.0 10.1 10.6 9.5 0.0 57.9 0.0 0.0 ... Apparently corr(d) from the boot-library fails with NAs in the data, also cor.test cannot cope with a
2006 Oct 03
1
postcript file / xyplot function [Broadcast]
This is FAQ 7.22. Lattice functions produce graphic objects, which are not displayed by default. If you print your graph, you should be fine. Also, take a look at the documentation for panel.xyplot. Using type = c("p", "r") should make things simpler. Regards, Matt Wiener -----Original Message----- From: r-help-bounces at stat.math.ethz.ch [mailto:r-help-bounces at
2008 Aug 18
1
"nested" getInitial calls; variable scoping problems
Hi All, Another nls related problem (for background, I'm migrating a complicated modelling package from S-plus to R). Below I've reduced this to the minimum necessary to demonstrate my problem (I think); the real situation is more complicated. Two similar selfStart functions, ssA and ssB. The 'initial' function for ssB modifies its arguments a little and then calls getInital
2010 Oct 17
4
Variable name as string
Hello, from Verzani, simpleR (pdf), p. 80, I created the following function to test the coefficient of lm() against an arbitrary value. coeff.test <- function(lm.result, var, coeffname, value) { # null hypothesis: coeff = value # alternative hypothesis: coeff != value es <- resid(lm.result) coeff <- (coefficients(lm.result))[[coeffname]] # degrees of freedom = length(var) -
2007 May 18
2
time series
Dear all, I am working with a data file which is the record of precipitation measurement normaly done every 10 minutes. I would like to check if there are missing times in my data file. Is there a function existing able to check for that in R ? Thanks by advance, Jessica
2010 Nov 16
2
Integrating functions / vector arithmetic
Hello, I was trying to build some functions which I would like to integrate over an interval using the function 'integrate' from the 'stats' package. As an example, please consider the function h(u)=sin(pi*u) + sqrt(2)*sin(pi*2*u) + sqrt(3)*sin(pi*3*u) + 2*sin(pi*4*u) Two alternative ways to 'build' this function are as in f and g below: coeff<-sqrt(1:4)
2008 Aug 11
3
Peoblem with nls and try
Hello, I can`t figure out how can increase the velocity of the fitting data by nls. I have a long data .csv I want to read evry time the first colunm to the other colunm and analisy with thata tools setwd("C:/dati") a<-read.table("Normalizzazione.csv", sep=",", dec=".", header=F) for (i in 1:dim(a[[2]]]) { #preparazione dati da analizzare
2008 Oct 15
1
Parameter estimates from an ANCOVA
Hi all, This is probably going to come off as unnecessary (and show my ignorance) but I am trying to understand the parameter estimates I am getting from R when doing an ANCOVA. Basically, I am accustomed to the estimate for the categorical variable being equivalent to the respective cell means minus the grand mean. I know is the case in JMP - all other estimates from these data match the
2011 Feb 08
4
Interactions in a nls model
I am interested in testing two similar nls models to determine if the lines are statistically different when fitted with two different data sets; one corn, another soybean. I know I can do this in linear models by testing for interactions. See Introductory Statistics with R by Dallgaard p212-218 for an example. I have two different data sets I am comparing to lai. ci.re should have very
2010 Nov 03
2
memory allocation problem
Hi R users I am trying to run a non linear parameter optimization using the function optim() and I have problems regarding memory allocation. My data are in a dataframe with 9 columns. There are 656100 rows. >head(org_results) comb.id p H1 H2 Range Rep no.steps dist aver.hab.amount 1 1 0.1 0 0 1 100 0 0.2528321
2006 Aug 21
4
question about 'coef' method and fitted_value calculation
Dear all, I am trying to calculate the fitted values using a ridge model (lm.ridge(), MASS library). Since the predict() does not work for lm.ridge object, I want to get the fitted_value from the coefficients information. The following are the codes I use: fit = lm.ridge(myY~myX,lambda=lamb,scales=F,coef=T) coeff = fit$coef However, it seems that "coeff" (or "fit$coef") is
2011 Mar 01
1
theora encoder reordering, order of puting data from DCT 8x8 blocks to huffman compressor, and puting result of huffman compressor to buffer bitstream memory
Good day! I'm creating HDL IP CORE (for using in FPGA) for theora encoder (now only I-frames). I don't undestand one moment. Now i develop such stages: 1. From RBG(byer) to YCbCr converter 2. DCT processing (8x8 pixels blocks) 3. Quantizator of DCT coeff. 4. Zig-Zag of quantized DCT coeff. and now i have uresolved last stage of compression - how i must send 8x8 blocks to huffman
2008 Sep 09
1
Genmod in SAS vs. glm in R
Hello, I have different results from these two softwares for a simple binomial GLM problem. >From Genmod in SAS: LogLikelihood=-4.75, coeff(intercept)=-3.59, coeff(x)=0.95 >From glm in R: LogLikelihood=-0.94, coeff(intercept)=-3.99, coeff(x)=1.36 Is there anyone tell me what I did wrong? Here are the code and results, 1) SAS Genmod: % r: # of failure % k: size of a risk set data
2007 Jun 06
1
spgrass6 and aggregation (bis)
Dear all, I have some additionale question concerning the spgrass6 package. * When you set a region in GRASS, does the readGRASS6 function in R only load data contained in the zoomed region or the whole map ? * When you have a MASK map in grass, does the readGRASS6 function in R only load data contained inside the MASK area ? Could this be the problem ? Thanks, Jessica