similar to: functions for subsets: a minor R programming challenge

Displaying 20 results from an estimated 9000 matches similar to: "functions for subsets: a minor R programming challenge"

2010 Sep 13
2
post
Hello, I have a question regarding how to speed up the t.test on large dataset. For example, I have a table "tab" which looks like: a b c d e f g h.... 1 2 3 4 5 ... 100000 dim(tab) is 100000 x 100 I need to do the t.test for each row on the two subsets of columns, ie to compare a b d group against e f g group at each row. subset 1: a b d 1 2 3 4 5 ... 100000
2005 Oct 03
1
storage.mode, C data types and speed
Hi, I am trying to speed up part of an algorithm in which certain columns of a large matrix (X) are replaced by the element-wise product of a matrix (M) and a vector (v). In R, the code might be X[, ind] <- M * v I have written a small C routine to do this for me, but the timing depends on how I define the storage.mode of the objects in R and the data types in C, in a way which I don't
2011 Sep 27
1
array extraction
hello everyone. Look at the following R idiom: a <- array(1:30,c(3,5,2)) M <- (matrix(1:15,c(3,5)) %% 4) < 2 a[M,] <- 0 Now, I think that "a[M,]" has an unambiguous meaning (to a human). However, the last line doesn't work as desired, but I expected it to...and it recently took me an indecent amount of time to debug an analogous case. Just to be explicit, I would
2010 Jun 01
1
BreastCancer Dataset for Classification in kknn
Dear All, I'm getting a error while trying to apply the BreastCancer dataset (package=mlbench) to kknn (package=kknn) that I don't understand as I'm new to R. The codes are as follow: rm = (list = ls()) library(mlbench) data(BreastCancer) library(kknn) BCancer = na.omit(BreastCancer) d = dim(BCancer)[1] i1 = seq(1, d, 2) i2 = seq(2, d, 2) t1 = BCancer[i1, ] t2 =
2009 Jun 10
2
How to get the unique pairs of a set of pairs dataframe ?
Hi friends, Please can anyone help me with an easier solution of doing the below mentioned work. Suppose i have a dataset like this:--- i1 i2 i3 i4 i5 1 7 13 1 2 2 8 14 2 2 3 9 15 3 3 4 10 16 4 4 5 11 17 5 5 6 12 18 6 7 *i1,i2,i3,i4,i5 are my items.I am able to find all possible pairs i.e Say this dataframe is "item_pairs" **i1,i2 **i1,i3 **i1,i4 i1,i5 **i2,i1
2013 Jan 02
0
[LLVMdev] [DragonEgg] [Polly] Should we expect DragonEgg to produce identical LLVM IR for identical GIMPLE?
Hi Duncan & Tobi, Thanks a lot for your interest, and for pointing out differences in GIMPLE I missed. Attached is simplified test case. Is it good? Tobi, regarding runtime alias analysis: in KernelGen we already do it along with runtime values substitution. For example: <------------------ __kernelgen_main_loop_17: compile started ---------------------> Integer args substituted:
2007 Dec 06
1
finding most highly transcribed genes - ranking, sorting and subsets?
Hello, I am not only interested in finding out which genes are the most highly up- or down-regulated (which I have done using the linear models and Bayesian statistics in Limma), but I also want to know which genes are consistently highly transcribed (ie. they have a high intensity in the channel of interest eg. Cy5 or Cy3 across the set of experiments). I might have missed a straight forward
2010 Jan 14
2
Fixed size permutations
I'm using functions to return a matrix of all permutations of a specified size from a larger list for predictor selection. For each predictor size I use a seperate function like this: bag2 <- function(n) { rl <- c() for (i1 in seq(n)) { for (i2 in seq(n)) { if (length(unique(c(i1,i2)))==1) {next} rl <- cbind(rl,matrix(c(i1,i2))) } }
2017 Sep 25
3
What should a truncating store do?
On 9/25/2017 9:14 AM, Björn Pettersson A wrote: > > (Not sure if this exactly maps to “truncating store”, but I think it > at least touches some of the subjects discussed in this thread) > > Our out-of-tree-target need several patches to get things working > correctly for us. > > We have introduced i24 and i40 types in ValueTypes/MachineValueTypes > (in addition to
2017 Sep 25
0
What should a truncating store do?
(Not sure if this exactly maps to “truncating store”, but I think it at least touches some of the subjects discussed in this thread) Our out-of-tree-target need several patches to get things working correctly for us. We have introduced i24 and i40 types in ValueTypes/MachineValueTypes (in addition to the normal pow-of-2 types). And we have vectors of those (v2i40, v4i40). And the byte size in our
2007 Dec 30
2
refering to variable names in lm where the variable name is in another variable
I am trying to refer to a variable name in a lm regression where the variable name is in another variable, but it does seem to work. Here is an example: y<-rnorm(10) dat<-data.frame(x1=rnorm(10),x2=rnorm(10),x3=rnorm(10)) nam<-c('x1','x2','x3') library(gtools) com<-combinations(3,2,1:3) mod<-lm(y~nam[com[1,1]],data=dat) #error in model frame....:variable
2008 Dec 07
1
[LLVMdev] How to extract loop body into a new function?
False Alarm!! Still don't know how to do it! I am trying to write a transformation pass to extract a loop body into a function. For example: The Loop in question is: for (i2 = 0; i2 < LOOP_SIZE; i2++) { A[B[i2]] = 2 * B[i2]; } The IR for which is: bb13: ; preds = %bb13, %bb %i2.0.reg2mem.0 = phi i32 [ 0, %bb ], [ %indvar.next62, %bb13 ] ; <i32>
2009 Jul 20
1
Regression function lm() not giving proper results
* * Hi , Can anyone help me please with this problem?* * *CASE-I* all_raw_data_NAomitted is my data frame.It has columns with names i1 ,i2, i3,i4…, till i15.It has 291 rows actually ,couldn’t show here. The data frame looks like this:-- i1 i2 i3 i4 i5 i6 i7 i8 i9 i10 i11 i12 i13 i14 i15 2 2 2 2 2 2 2 2 2 2 2 1 2 2 3 2 3 2 2 2 2 3 2 2 3 3
2003 Sep 25
1
apply on a 4D array
I am trying to multiply a 3D array of 4x4x4 by the 4 3D arrays of a 4D array with dimensions 4x4x4x4 (the last dimension being the one that I want to split by). (4x4x4 array) > hiaAry , , a1 i1 i2 i3 i4 h1 9.5936098 6.001040 0.08772 0.3138600 h2 1.2003500 1.454570 2.79248 0.0000000 h3 0.1346500 0.201220 0.39256 0.5464000 h4 0.0109000 0.012270 0.16417 0.2766900 ,
2006 Nov 21
1
lme4 model with no fixed effects?
Crossed random effects: > lmer( y ~ (1 | i1) + (1|i2) ,data=dta) Linear mixed-effects model fit by REML Formula: y ~ (1 | i1) + (1 | i2) Data: dta AIC BIC logLik MLdeviance REMLdeviance 91.18 94.84 -42.59 85.2 85.18 Random effects: Groups Name Variance Std.Dev. i1 (Intercept) 0.068224 0.26120 i2 (Intercept) 0.463112
2010 Dec 31
4
Repeated Indexing / Sequence Operation
Hi Everyone, quick question before the end of the year. I have soem indices to select data from a bigger sample. I want to select n days before each index and n days after the index. Any clever way to do it. A for loop would do but I wanted to know if there is a moreR-friendly way to approach this Example # InitialIndices i2 = (90, 190, 290) # Indices I want to end up with i3 = c(85, 86, 87,
2010 Aug 03
2
How to name matrices from a list with lapply ?
Dear list, I have a list of matrices : i1 <- matrix(1:10, nrow = 2, ncol = 5) i2 <- matrix(11:20, nrow = 2, ncol = 5) j <- list(i1 = i1, i2 = i2) I would like to attribute names to each dimension, for each matrix, as follows : $i1 B1 B2 B3 B4 B5 A1 1 3 5 7 9 A2 2 4 6 8 10 $i2 B1 B2 B3 B4 B5 A1 11 13 15 17 19 A2 12 14 16 18 20 However, I have to use lapply function and attribute
2008 May 08
1
Reading multiple tables from file
Dear R-users, I have output files having a variable number of tables in the following format: ------------- 1 Pietje I1 I2 Value 1 1 0.11 1 2 0.12 2 1 0.21 2 Jantje I1 I2 I3 Value 1 1 1 0.111 3 3 3 0.333 ... ------------- Would there be an easy way of turning this into (a list of) data.frames with names Pietje, Jantje and variables I1,I2,...Value? (I1,I2 are string or categorical,
2016 May 16
2
Determination of statements that contain only matrix multiplication
Hi Tobias, could we use information about memory accesses of a SCoP statement and def-use chains to determine statements, which don’t contain matrix multiplication of the following form? for (int i = 0; i < Upper Bound1; i++) for (int j = 0; j < Upper Bound2; j++) for (int k = 0; k < Upper Bound3; j++) C[i][j] += A[i][k] * B[k][j] We could probably check that memory access
2012 Jan 27
2
The following code (using rgamma) hangs
Hi, I'm seeing something that may be a bug in R's standalone math library, which is packaged by Debian as r-mathlib. I reported it to the Debian BTS as http://bugs.debian.org/657573 I'm using Debian squeeze, and the code was tested with r-mathlib 2.11.1-6 (default on stable) and 2.14.1-1 (from testing/unstable). I summarize this report below. The following code with the R math