similar to: dist function in R is very slow

Displaying 20 results from an estimated 4000 matches similar to: "dist function in R is very slow"

2017 Jun 18
2
dist function in R is very slow
Hi Stefan, Thank you very much for pointing me to the wordspace package. It does the job a bit faster than my C code but is 100 times more convenient. By the way, since the tcrossprod function in the Matrix package is so fast, the Euclidean distance can be computed very fast: euc_dist <- function(m) {mtm <- Matrix::tcrossprod(m); sq <- rowSums(m*m);? sqrt(outer(sq,sq,"+") -
2017 Jun 18
0
dist function in R is very slow
> By the way, since the tcrossprod function in the Matrix package is so fast, the Euclidean distance can be computed very fast: Indeed. > euc_dist <- function(m) {mtm <- Matrix::tcrossprod(m); sq <- rowSums(m*m); sqrt(outer(sq,sq,"+") - 2*mtm)} There are two reasons why I didn't use this optimization in "wordspace": 1) It can be inaccurate for small
2012 Jun 16
1
Efficient distance calculation on big matrix
Hi All, I'm working on analyzing a large data set, lets asume that dim(Data)=c(1000,8700). I want to calculate the canberra distance between the columns of this matrix, and using a toy example ('test' is a matrix filled with random numbers 0-1): > system.time(d<-as.matrix(dist(t(test), method = "canberra", diag = FALSE, upper = FALSE, p = 2))) user system
2011 Apr 02
3
Plotting MDS (multidimensional scaling)
Hi, I just encountered what I thought was strange behavior in MDS. However, it turned out that the mistake was mine. The lesson learned from my mistake is that one should plot on a square pane when plotting results of an MDS. Not doing so can be very misleading. Follow the example of an equilateral triangle below to see what I mean. I hope this helps others to avoid this kind of headache.
2010 Jan 21
2
"stack imbalance in ..." when loading a workspace
Hi all, I just failed in loading a saved wordspace (13MB of size), and received these errors: Warning: stack imbalance in 'missing', 52 then 51 Warning: stack imbalance in 'if', 50 then 53 Warning: stack imbalance in 'as.environment', 57 then 59 Warning: stack imbalance in 'ls', 54 then 53 Warning: stack imbalance in '.Internal', 54 then 53 Warning: stack
2012 Sep 04
10
Generic asset definitions and management
(The following is not a Rails-specific question, but relates to a problem that affects Rails, so I wonder whether anyone on the team has an opinion about it or knows whether a solution is already in development.) While gem dependencies can be easily managed in a Gemfile by Bundler, when it comes to other assets, you either have to manually copy javascript files into the app/assets or vendor
2007 Jun 14
3
Responding to a posting in the digest
Is there a convenient way to respond to a particular posting which is a part of the digest? I mean something that will automatically quote the original message, subject, etc. Thank you! Moshe Olshansky m_olshansky at yahoo.com
2011 Jan 31
1
rgl: draw multiple ellipsoids
Dear list, I'm trying to visualise some ellipsoidal shapes in 3D. Their position, axes, and angular orientation can be arbitrary. I saw an ellipse3d function in rgl; however it is heavily oriented towards the statistical concept of ellipse of confidence, whilst I am just concerned with the geometrical object. Below is my current implementation. It is quite slow when creating many shapes, so
2008 Jul 10
5
rounding
Hi, Round(0.55,1)=0.5 Round(2.55,1)=2.6 Can this be right? Thanks, Ed [[alternative HTML version deleted]]
2003 Sep 26
2
polar plotting of complex quantities
Hello to everybody, ... and sorry if the question has already been answered. I am dealing with complex numbers and need a way of plotting them on angular plots (2D and 3D). Is there a package that already manage this, or can somebody in this R-world who could help me with his skill ? Thanks to all. Have a nice week-end ! Olivier Eterradossi Ph.D., "PsychoSensory Properties of
2007 Jun 09
4
Prototype Question
I''m trying to apply a css class to all LI elements that are children of an element with the ID "idSelector". This is what I did and it works. But I was wondering if there was an easier way without having to use an anonymous function? $$("#idSelector li").each(function() { arguments[0].addClassName("myClass") }); Thanks in advance.
2012 Dec 12
3
Fw: regarding plot
Hello, i am working in origin pro, i want to plot a graph as like a pdf attached but with black and white lines. here radial axis varies from 0 to 1. and angular axis from 0 degree to 60 degree.and third axis which is depend on both radial and axial gives non intersecting lines. how can i read the data from plot for replot. vikas -------------- next part -------------- A non-text attachment was
2008 Aug 24
3
Igraph library: How to calculate APSP (shortest path matrix) matrix for a subset list of nodes.
Dear R Users, I have a network of 25000 total nodes and a list of 500 node which is a subset of all nodes. Now I want to calculate the APSP (all pair shortest path) matrix only for these 500 nodes. I would appreciate any help. Thanks in advance Dinesh -- Dinesh Kumar Barupal Research Associate Metabolomics Fiehn Lab UCD Genome Center 451 East Health Science Drive GBSF Builidng University of
2002 Nov 11
3
Wind roses
Are there any R function or packages that generate wind roses? These are ``star''-like plots that summarize the frequency, direction and magnigude of windspeeds. Thanks, Matt -- Matt Pocernich University of Colorado - Denver Department of Mathematics -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read
2004 Aug 06
1
Fixed-point cos/acos
Hi, Before I try to code this myself, I'd like to know if anyone has a fixed-point routine to compute the cos and acos functions. All I need is around 3-digit accuracy. Thanks. Jean-Marc -- Jean-Marc Valin, M.Sc.A., ing. jr. LABORIUS (http://www.gel.usherb.ca/laborius) Université de Sherbrooke, Québec, Canada -------------- next part -------------- A non-text attachment was
2017 May 24
2
System Time Source
On Wed, May 24, 2017 10:45 am, Warren Young wrote: > On May 24, 2017, at 8:52 AM, Chris Adams <linux at cmadams.net> wrote: >> >> Once upon a time, Warren Young <warren at etr-usa.com> said: >>> a. It???s transmitting from a fixed location in a time zone you >>> probably aren???t in ??? US Mountain ??? being the least populous of >>> the lower
2008 Nov 17
2
How to calculate the linear distance between 2 points
Deemed colleagues I would appreciate your help with a sentence to calculate the linear distance between 2 geographical points (coordinates in UTM). In advance thnks for your attention, -- Ricardo Bandin Llanos rbandin@udec.cl Estudiante - Magíster Cs. m. Pesquerías Universidad de Concepción, Región del Bio-Bio, Chile Celular: (0056-41) 97949957 [[alternative HTML version deleted]]
2007 Aug 07
5
small sample techniques
If my sample size is small is there a particular switch option that I need to use with t.test so that it calculates the t ratio correctly? Here is a dummy example? á =0.05 Mean pain reduction for A =27; B =31 and SD are SDA=9 SDB=12 drgA.p<-rnorm(5,27,9); drgB.p<-rnorm(5,31,12) t.test(drgA.p,drgB.p) # what do I need to give as additional parameter here? I can do it manually but
2004 Jan 06
2
dist(x,y)
Hi Ryszard! There is a dist function in R. It's in the mva package. You can set the kind of distance that you want. Thanks, Erin mailto:hodgess at gator.uhd.edu
2013 Oct 03
1
Random Projection
Hello: I was wondering, has anyone has encountered an R package that performs random projection/random mapping? RP is a procedure that is akin to Principal Components Analysis in that it accomplishes dimensionality reduction, but is far more computationally efficient. I have been searching for some time, but haven't seen anything on CRAN-r yet. David Monaghan Sociology Ph.D. Candidate,