similar to: matrix help (first occurrence of variable in column)

Displaying 20 results from an estimated 800 matches similar to: "matrix help (first occurrence of variable in column)"

2009 Mar 12
3
help with predict and plotting confidence intervals
Dear R help, This seems to be a commonly asked question and I am able to run examples that have been proposed, but I can't seems to get this to work with my own data. Reproducible code is below. Thank you in advance for any help you can provide. The main problem is that I can not get the confidence lines to plot correctly. The secondary problem is that predict is not able to find my object
2009 Apr 15
3
Kruskal's MDS results
Dear List, I'm trying to interpret the results of the Kruskal's Non-metric Multidimensional Scaling algorithm (isoMDS, MASS package). The 'goodness of fit' is reported as "The final stress achieved (in percent)". What does this mean exactly? I've tried to google for an answer but I've not come up with a definitive answer. Regards, Dieter -- Dieter Vanderelst
2010 Feb 14
1
Dimensional reduction package
Is there any R package which implements non-linear dimensionality reduction (LLE, ISOMAP, GTM, and so on) and/or intrinsic dimensionality estimation ? Thank you, Maura tutti i telefonini TIM! [[alternative HTML version deleted]]
2010 Mar 02
1
how to import map data (maptools?) from a html set of 'coords'
Dear R users, I would like to draw map and import it in maptools/spatstat packages. The 'raw data' I have come from a web page (<map>...</map>) and are basically a list of coordinates of a polygon. I would like to know how to import them in R; I checked the maptools packages, but all the examples use existing .dbf files. I just have a (serie of) text file(s) looking like
2010 Feb 12
1
Problems with savePlot() and postscript under Snow Leopard
Dear all, I tried: > iris > species.n <- as.numeric(Species) > plot(iris, col = species.n) > savePlot(filename="IrisTestPlot", type="png") and got the error message: Fehler in savePlot(filename = "IrisTestPlot", type = "png") : kann nur aus 'X11(type="*cairo")' Devices kopieren (sorry, I have a german version of R). I
2009 Dec 14
1
lapply , mapply questions
Dear all, i have a programming problem that should be simple, though i am stuck with it. Please note that this is not a specific geonames problem, though i use it as an example - it´s just a basic problem with lapply. I use the geonames webservices with the R geonames packages which works almost smoothly. I have a vector of Zipcodes and i want to do a geonames lookup for all of them, which
2010 Apr 02
2
Biplot for PCA using labdsv package
Hi everyone, I am doing PCA with labdsv package. I was trying to create a biplot graphs in order to observe arrows related to my variables. However when I run the script for this graph, the console just keep saying: *Error in nrow(y) : element 1 is empty; the part of the args list of 'dim' being evaluated was: (x)* could please someone tell me what this means? what i am doing
2010 May 25
2
Calculation time of isoMDS and the optimal number of dimensions
Dear all, I'm running a set of nonparametric MDS analyses, using a wrapper for isoMDS, on a 800x800 distance matrix. I noticed that setting the parameter k to larger numbers seriously increases the calculation time. Actually, with k=10 it calculates already longer than for k=2 and k=5 together. It's now calculating for 6 hours, and counting... There is quite a difference between the
2009 Aug 02
1
package to convert coordiantes to timezone
Is there a R-package with a function that returns me the timezone, if I hand over longitude and latitude? I know online services like http://ws.geonames.org/timezone?lat=-38.01&lng=147 and http://www.earthtools.org/webservices.htm#timezone and wodner if this exists for R too. Thanks for helping, thomas
2011 May 10
3
metaMDS and envfit: Help reading output
Hello R experts, I've used metaMDS to run NMDS on some fish abundance data, and am also working on correlating environmental data to the NMDS coordinates. I'm fairly new to metaMDS and NMDS in general, so I have what are probably some very basic questions. My fish abundance data consists of 66 sites for which up to 20 species of fish were identified and counted. I ran metaMDS on this data
2010 Jan 25
4
R Output and ArcGIS
Dear all, I've been using R on a Mac to process some data for export to ArcMap GIS (which only runs on Windows). ArcMap seems to require tab-delimited data (my data are in 3 columns), so I've been using the sep="\t" argument. However, this resulted in strange end-of-line characters when displayed on a PC. I looked in the write.table help file to find that eol="\r\n"
2010 Apr 05
4
NMDS Ordination Graphics Problem
Dr. Stevens, Hi, my name is Trey Scott, and I'm a grad student of Brian McCarthy's. He referred me to you because of your expertise in handling complex R problems. We were hoping you could help us solve a nagging problem that is prohibiting me from producing graphicl output. Here is a simple mock-up of the matrix I'm using a b c d e f 1i 1 4
2009 Jan 21
1
vegan metaMDS
Hi, I'm trying to use metaMDS with a dissimilarity matrix of angles, not Bray-Curtis, and I wanted to know if there is an in-built function to produce a plot of stress values against dimensions, that could be used to determine the 'true' dimension of the solution. The number of objects is only a lowly 8 so any solution higher than 2-dimensional is not likely to be interpretable,
2012 Mar 29
1
Retrieving matrix column and row names by index value
Hi all, So let's say I have a matrix, mdat and I only know the index number. How do I retrieve the column and row names? For example, > mdat <- matrix(c(1,2,3, 11,12,13), nrow = 2, ncol=3, byrow=TRUE, dimnames = list(c("row1", "row2"), c("C.1", "C.2", "C.3"))) > mdat[4] [1] 12 >
2010 Sep 18
2
feedback/question on function update()
Hi, First let me say I am a big fan of R and appreciate all your time and effort. The update() function does not seem to work in a for loop. Consider the following: mdat <- matrix(c(1,2,3, 11,23,13, 12,4,8), nrow = 3, ncol=3, byrow=TRUE) reg <- lm(mdat[7:9]~1) for(i in 1:2) { reg <- update(reg,.~.+mdat[((i-1)*3 + 1):(i*3)]) #update reg twice } reg # reg should have two independent
2009 Mar 05
3
Dropping rows conditionally
Dear R-help team, I am getting addicted to using R but keep on getting many challenges on the way especially on data management (data cleaning). I have been wanting to drop all the rows if there values are `NA' or have specific values like 1 or 2 or 3. mdat <- matrix(1:21, nrow = 7, ncol=3, byrow=TRUE, dimnames = list(c("row1",
2009 Jan 26
1
reshape problem: id and variable names not being recognized
Hi everyone. Long time listener, first-time caller here. I have a data set that's been melted with the excellent reshape package, but I can't seem to cast it the way I need to. Here's the melted data's structure: > str(mdat) 'data.frame': 6978 obs. of 4 variables: $ VehType : Factor w/ 2 levels "Car","Truck": 1 1 2 1 1 2 1 1 1 1 ... $ Year :
2011 Nov 11
1
barplot names.arg
Hello there, I have a question regarding bar plots. I am trying to plot the data from the following matrix as a barplot - # input data mdat <- matrix(c(0.1,0.9,0.9,0.1,0.5,0.5,0.45,1-0.45,0.6,0.4,0.8,0.2), nrow = 6, ncol=2, byrow=TRUE, + dimnames = list(c("Mon", "Mon", "Tues", "Tues", "Thurs", "Friday"), +
2010 Mar 02
16
Three most useful R package
Hi R-fans, I would like put out a question to all R users on this list and hope it will create some feedback and discussion. 1) What are your 3 most useful R package? and 2) What R package do you still miss and why do you think it would make a useful addition? Pulling answers together for these questions will serve as a guide for new users and help people who just want to get a hint where to
2005 Jan 06
5
How to avoid rounding of matrix elements?
Hi all R-users, If I have a matrix with numeric elements as follows, the values are rounded when I try to refer to a specifici element using [], the value is rounded. The same thing happens if the matrix is read from a file, the values are stored to the correct precision but then when I try to refer to a specific element (such as using [], it is rounded. How do I avoid this rounding?