similar to: Avoiding loops

Displaying 20 results from an estimated 20000 matches similar to: "Avoiding loops"

2010 Mar 23
1
information module Wilks' lambda criterion
Hi everybody, I was wondering if you can help me about a module. In fact, I'm looking for a package or module about Wilks' lambda criterion in R environment. I didn't find it in R website ( http://cran.cict.fr/web/packages/index.html#available-packages-W or http://search.cpan.org/faq.html). If this module exists, could you show me the command line. Thank you very much for your help,
2009 Nov 20
3
help me avoid nested for() loops!
Hi R folks, I have a massive array (object name "points") in the following form [,1] [,2] [1,] 1369 22 [2,] 1370 22 [3,] 1368 23 [4,] 1369 23 [5,] 1370 23 [6,] 1371 23 (10080 rows truncated) These represent pixel coordinates of interest in a jpeg image. I need to find the distance from each point to all other points of interest. The only way I can see to do this
2006 Mar 12
1
alias_method interferes ApplicationHelper
Hello, I''m using Ruby 1.8.4 (darwinport), rails-1.0.0 (gem) , Powerbook / Mac OS X 10.4.5 , Webrick. How come Rails always raises NoMethodError for my helper (must_fill and rp or number_to_currency_rp) in application_helper.rb ? I doubt that alias_method is the culprit, but if i give # comment then there will be no errors at all ... :/ what am i doing wrong? is it a bug or stupid me? Thx
2006 Dec 31
4
Does SQL group by have a heavy duty equivalent in R
I have hundreds of humans who have undergone SNP genotyping at hundreds of loci. Some have even undergone the procedure twice or thrice (kind of an internal control). So obviously I need to find those replications, and confirm that the results are the same. If there is discordance then I need to address it. I tried to use the aggregate function nr.attempts
2008 Dec 09
2
Better way to find distances between points in a set?
I was playing around a bit to see how I could find the two points in a set of points (or ordered pairs) furthest from each other. Here's what I did: 1) created a Nrow by 2col matrix, so each row contains an x,y coordinate pair. 2) fed the matrix to a nested mapply (cv is my matrix): mapply(function(k,l) mapply(function(x,y,a,b) +
2010 Aug 04
2
discrete ECDF
Dear list; I just created a utility function that replicates what I have done in the past with Excel or OO.org by putting a formula of the form =sum($A1:A$1) in an upper-corner of a section and then doing a "fill" procedure by dragging the lower-rt corner down and to the right. When divided by the grand sum of the entries this function then calculates a 2D-discrete-ECDF. I
2008 Dec 22
2
How can I avoid nested 'for' loops or quicken the process?
Hi All, I'm still pretty new to using R - and I was hoping I might be able to get some advice as to how to use 'apply' or a similar function instead of using nested for loops. Right now I have a script which uses nested for loops similar to this: i <- 1 for(a in Alpha) { for (b in Beta) { for (c in Gamma) { for (d in Delta) { for (e in Epsilon) { Output[i] <-
2010 Jun 26
3
converting result of substitute to 'ordidnary' expression
Dear R users, As substitute() help page points out: Substituting and quoting often causes confusion when the argument is 'expression(...)'. The result is a call to the 'expression' constructor function and needs to be evaluated with 'eval' to give the actual expression object. And indeed I am confused. Consider: > dat <- data.frame(x=1:10,
2010 Jun 26
3
converting result of substitute to 'ordidnary' expression
Dear R users, As substitute() help page points out: Substituting and quoting often causes confusion when the argument is 'expression(...)'. The result is a call to the 'expression' constructor function and needs to be evaluated with 'eval' to give the actual expression object. And indeed I am confused. Consider: > dat <- data.frame(x=1:10,
2010 Nov 04
2
count occurrence and distance of characters in string
Hello all, I want to know how often one character occurs in a given string and the distance from between every two occurences. (distance = other characters between them). thanks
2011 Feb 17
2
sort by column and row names
Hello, All, How can one sort on column and row names. For example: How can this X1 X3 X2 X1 1 0 0 X3 0 1 0 X2 0 0 1 become this? X1 X2 X3 X1 1 0 0 X2 0 1 0 X3 0 0 1 Thank you for your time! Jim [[alternative HTML version deleted]]
2010 Jul 28
2
read.delim()
I am reading in a very large file with names in it and R is truncating the number of rows it reads in. The separator in this file is a pipe '|' and so I use dat <- read.delim('pathToMyFile', header= TRUE, sep='|') It turns out that it is reading up to row 61145 and stopping and I think I see why, but am not sure of the best solution to this problem. I see the name of
2009 Jul 30
3
Looping through R objects with $ operator and tags
Hi all, Suppose I want to set the values in a column to the log of the values of another column like so: object$LogDist <- log10(object$Distance) How do I loop through the objects if I have object1, object2, etc to perform this function? object1$LogDist <- log10(object1$Distance) object2$LogDist <- log10(object2$Distance) object3$LogDist <- log10(object3$Distance) I was trying to
2010 Feb 13
2
lm function in R
Hello, I am trying to learn how to perform Multiple Regression Analysis in R. I decided to take a simple example given in this PDF: http://www.utdallas.edu/~herve/abdi-prc-pretty.pdf I created a small CSV called, students.csv that contains the following data: s1 14 4 1 s2 23 4 2 s3 30 7 2 s4 50 7 4 s5 39 10 3 s6 67 10 6 Col headers: Student id, Memory span(Y), age(X1), speech rate(X2) Now
2008 Aug 06
4
defining the distance between axis label and axis
Hi, How can I make the distance between an axis-label and the axis bigger? I haven't found anything in par()...
2008 Dec 10
1
subset point data set by distance ranges
Greetings I'm using R 2.8 with recent (last month) versions of the packages I need to use at present. I'm interested in examining hierarchical spatio-temporal patterns in a data set. The data consist of 94 points (X, Y, UTM coordinates) at which catch rates for a fish were recorded and there are also estimates of prey available for these fish at the same locations.
2007 Oct 20
2
formatting a list
Hi, I am new to R and need to read in a file with 19 columns and 7000 rows and make it into a list of 7000 lists with 19 items each. For a simpler case of 10 by 10 table I used x <-scan("file", list(0,0,0,0,0,0,0,0,0,0)), perhaps clumsy, but it did the job. However with the large 19x7000 (which needs to be transposed) I am not sure how to go about it. Coudl somebody suggest a way?
2011 Jan 08
3
Question on list objects
Hi, I have 2 questions on list object:   1. Suppose I have a matrix like: dat <- matrix(1:9,3)   Now I want to replicate this entire matrix 3 times and put entire result in a list object. Means, if "res" is the resulting list then I should have:   res[[1]]=dat, res[[2]]=dat, res[[3]]=dat   How can I do that in the easilest manner?   2. Suppose I have 2 list objects: list1 <- list2
2012 Apr 30
2
Generate Dendrogram
Hi I have a distance matrix which is computed by user defined method. I would like to plot the dendrogram. I would like to use different color and want the leaves laying down bottom. The script like this. I am not familiar with R. I followed the example shown in http://stat.ethz.ch/R-manual/R-devel/library/stats/html/dendrogram.html dist.obj <- as.dist(matrix.distance) hc.obj <-
2009 Nov 17
1
hclust too slow?
Hi, I am new to clustering in R and I have a dataset with approximately 17,000 rows and 8 columns with each data point a numerical character with three decimal places. I would like to cluster the 8 columns so that I get a dendrogram as an output. So, I am simply creating a distance matrix of my data, using the 'hclust' function, and then plotting the results (see below, my data is