similar to: Using very large matrix

Displaying 20 results from an estimated 2000 matches similar to: "Using very large matrix"

2010 Mar 30
6
Error "singular gradient matrix at initial parameter estimates" in nls
I am using nls to fit a non linear function to some data. The non linear function is: y= 1- exp(-(k0+k1*p1+ .... + kn*pn)) I have chosen algorithm "port", with lower boundary is 0 for all of the ki parameters, and I have tried many start values for the parameters ki (including generating them at random). If I fit the non linear function to the same data using an external
2009 Sep 01
3
Strange error returned or bug in gam in mgcv????
Dear friends, what is this error message in gam???? I cannot understand what it means .... is it a bug? gam_bray_scot24_pc_0505<gam(bray~s(PC1,PC2,PC3,PC4,PC5, PC1.1,PC2.1,PC3.1,PC4.1,PC5.1),data=dist_scot24_vector_with_climate) Error in if (length(data) != vl) { : missing value where TRUE/FALSE needed Calls: gam ... smooth.construct -> smooth.construct.tp.smooth.spec -> array In
2009 Sep 30
3
A point in a vector?
Dear list, I have a strange requirement .... I have a vector, for example v<- c(0,0,0,0,1,2,4,6,8,8,8,8). I have a value,for example x<- 4.8. I would like to understand in which sub interval of v is x. In this case, v would be in the sub interval [4,6] that is in the subinterval starting from element j=7 to the element j+1=8. Can we do that with an R command? Regards -- Corrado Topi
2010 Mar 30
3
From THE R BOOK -> Warning: In eval(expr, envir, enclos) : non-integer #successes in a binomial glm!
Dear friends, I am testing glm as at page 514/515 of THE R BOOK by M.Crawley, that is on proportion data. I use glm(y~x1+,family=binomial) y is a proportion in (0,1), and x is a real number. I get the error: In eval(expr, envir, enclos) : non-integer #successes in a binomial glm! But that is exactly what was suggested in the book, where there is no mention of a similar warning. Where am I
2009 Sep 03
3
goodness of "prediction" using a model (lm, glm, gam, brt, regression tree .... )
Dear R-friends, How do you test the goodness of prediction of a model, when you predict on a set of data DIFFERENT from the training set? I explain myself: you train your model M (e.g. glm,gam,regression tree, brt) on a set of data A with a response variable Y. You then predict the value of that same response variable Y on a different set of data B (e.g. predict.glm, predict.gam and so on).
2009 Nov 25
3
Concave hull
Dear friends, Do you know how to calculate the CONCAVE hull of a set of points (2- dimensional or n-dimensional)? is that possible in R? (With a "smoothing" parameter of course). Best, -- Corrado Topi Global Climate Change & Biodiversity Indicators Area 18,Department of Biology University of York, York, YO10 5YW, UK Phone: + 44 (0) 1904 328645, E-mail: ct529 at york.ac.uk
2009 Sep 10
2
Negative AIC
Dear R list, I just obtained a negative AIC for two models (-221.7E+4 and -230.2E+4). Is that normal? Regards -- Corrado Topi Global Climate Change & Biodiversity Indicators Area 18,Department of Biology University of York, York, YO10 5YW, UK Phone: + 44 (0) 1904 328645, E-mail: ct529 at york.ac.uk
2008 Dec 11
2
Principal Component Analysis - Selecting components? + right choice?
Dear R gurus, I have some climatic data for a region of the world. They are monthly averages 1950 -2000 of precipitation (12 months), minimum temperature (12 months), maximum temperature (12 months). I have scaled them to 2 km x 2km cells, and I have around 75,000 cells. I need to feed them into a statistical model as co-variates, to use them to predict a response variable. The climatic
2009 Aug 24
2
Formulas in gam function of mgcv package
Dear R-experts, I have a question on the formulas used in the gam function of the mgcv package. I am trying to understand the relationships between: y~s(x1)+s(x2)+s(x3)+s(x4) and y~s(x1,x2,x3,x4) Does the latter contain the former? what about the smoothers of all interaction terms? I have (tried to) read the manual pages of gam, formula.gam, smooth.terms, linear.functional.terms but
2009 Aug 24
2
Formulas in gam function of mgcv package
Dear R-experts, I have a question on the formulas used in the gam function of the mgcv package. I am trying to understand the relationships between: y~s(x1)+s(x2)+s(x3)+s(x4) and y~s(x1,x2,x3,x4) Does the latter contain the former? what about the smoothers of all interaction terms? I have (tried to) read the manual pages of gam, formula.gam, smooth.terms, linear.functional.terms but
2009 Aug 27
19
Best R text editors?
Quick informal poll: what is everyone's favorite text editor for working with R? I'd like to hear from people who are using editors that have some level of direct R interface (e.g. Tinn-R, Komodo+SciViews). Thanks! --j -- Jonathan A. Greenberg, PhD Postdoctoral Scholar Center for Spatial Technologies and Remote Sensing (CSTARS) University of California, Davis One Shields Avenue The
2009 Oct 02
1
Fetch large sized file from SQL
Hi List, Does any one know what package I need to use in order to fetch/get a large sized dataframe from SQL? I have already used sqldf package which is good for fetching large sized csv files. Thanks Alireza [[alternative HTML version deleted]]
2010 Mar 23
1
S4: Multiple inheritance
Hi all, Working with S4 object, I definine two class foo1 and foo2. I define '[' (resp. '[<-') for the two classes. Then I define a third class foo3 that inherit from both foo1 and foo2. Is there a way to make '[' (resp. '[<-') for foo3 inherit from '[' (resp. '[<-') for foo1 and foo2? Thanks Christophe
2011 Apr 29
2
Summer student internship placement at University of York / YCCSA / SEI (paid)
Dear R-lings, I did not know which list to post to, because it is a studentship so not really a job, so it did not fit the r-sig-jobs list .... and it is about devloping an extension package interfaced with R .... I hope I did not upset anyone. If so apologies. The Centre For Complex systems Analysis at the University of York (YCCSA) in UK in collaboration with Stockholm Environment
2011 May 03
1
Visiting Researcher, species distribution modelling, Cali, Colombia
Dear All, The Decision and Policy Analysis (DAPA) program of the International Center for Tropical Agriculture (CIAT), a not-for-profit agriculture, biodiversity and ecosystems research center, supported by the Consultative Group of International Agricultural Research (CGIAR), with headquarters in Cali, Colombia is looking for a visiting researcher to work on various modeling projects, primarily
2009 Sep 29
4
Something wrong with my function Please Help
Hi R users, I try to build a function to compute odds ratio and relative risk however something wrong. I stuck for many hours but I really don't know how to solve it. Would someone please give me a hint? > OR.RR<-function(x){ + x <- as.matrix(any(dim(x)==2)) + OR<-(x[1,1]*x[2,2])/(x[1,2]*x[2,1]) + RR<-(x[1,1]/(sum(x[1,])))/(x[2,1]/(sum(x[2,]))) +
2010 Mar 23
1
Changing content of column in data.frame + efficient join extraction between 2 data.frames
Dear R users, I have 2 SpatialPointsDataFrame's, pcs and East. The column str_1 in the first (pcs) is: > pcs[0:4,] coordinates cat str_1 int_1 int_2 dbl_1 dbl_2 1 (101000, 263000) 1 "SM06B" 101000 263000 4.978915 -4.293668 2 (101000, 265000) 2 "SM06C" 101000 265000 4.960478 -4.266742 3 (101000, 267000) 3 "SM06D" 101000 267000
2009 Sep 15
5
identical(length(x), 1) returns FALSE, but print(length(x)) is 1, length(x)==1 is TRUE, and is.integer(lenght(x)) is TRUE????
Dear R, the condition: identical(length(x),1) returns FALSE but print(length(x)) returns 1 and: is.vector(x) is TRUE. is.integer(length(x)) is TRUE length(x) ==1 is TRUE I am puzzled. Regards -- Corrado Topi Global Climate Change & Biodiversity Indicators Area 18,Department of Biology University of York, York, YO10 5YW, UK Phone: + 44 (0) 1904 328645, E-mail: ct529 at york.ac.uk
2009 Sep 28
6
SAS user now converting to R - Help with Transpose
I am just starting to code in R and need some help as I am used to doing this in SAS. I have a dataset that looks like this: Chemical Well1 Well2 Well3 Well4 BOD 13.2 14.2 15.5 14.2 O2 7.8 2.6 3.5 2.4 TURB 10.2 14.6 18.5 17.3 and so on with more chemicals.... I would like to transpose my data so that it looks like this: Chemical WellID Value BOD Well1 13.2 BOD Well2 14.2 BOD Well3 15.5 BOD
2009 Sep 03
1
--enable-memory-profiling at configuration (compilation) time?
Dear Rfriends, what is the option --enable-memory-profiling at configuration (just before build + install) time? I did not find mention of it in the R admin manual (http://cran.r- project.org/doc/manuals/R-admin.html). Regards -- Corrado Topi Global Climate Change & Biodiversity Indicators Area 18,Department of Biology University of York, York, YO10 5YW, UK Phone: + 44 (0) 1904 328645,