similar to: define variables from rows of a matrix

Displaying 20 results from an estimated 11000 matches similar to: "define variables from rows of a matrix"

2011 Aug 13
2
define variables from a matrix
I have a following matrix and wish to define a variable based the variable A=matrix(0,5,5) A[1,]=c(30,20,100,120,90) A[2,]=c(40,30,20,50,100) A[3,]=c(50,50,40,30,30) A[4,]=c(30,20,40,50,50) A[5,]=c(30,50,NA,NA,100) > A [,1] [,2] [,3] [,4] [,5] [1,] 30 20 100 120 90 [2,] 40 30 20 50 100 [3,] 50 50 40 30 30 [4,] 30 20 40 50 50 [5,] 30 50 NA NA
2005 Feb 21
5
Compare rows of two matrices
Hello, #I have two matrices, eg.: y <- matrix( c(20, NA, NA, 45, 50, 19, 32, 101, 10, 22, NA, NA, 80, 49, 61, 190), ncol=4 ) x <- matrix( c(20, NA, NA, NA, 50, 19, 32, 101, 10, 22, NA, NA, 80, 49, 61, 190), ncol=4 ) #Whereas x contains all NA?s from y plus some additional NA?s. #I want to find the index of these additional NA?s. I think, there must be a very
2007 Mar 08
2
Removing duplicated rows within a matrix, with missing data as wildcards
I'd like to remove duplicated rows within a matrix, with missing data being treated as wildcards. For example > x <- matrix((1:3), 5, 3) > x[4,2] = NA > x[3,3] = NA > x [,1] [,2] [,3] [1,] 1 3 2 [2,] 2 1 3 [3,] 3 2 NA [4,] 1 NA 2 [5,] 2 1 3 I would like to obtain [,1] [,2] [,3] [1,] 1 3 2 [2,] 2 1 3
2017 Dec 20
2
outlining (highlighting) pixels in ggplot2
Using the small reproducible example below, I'd like to know if one can somehow use the matrix "sig" (defined below) to add a black outline (with lwd=2) to all pixels with a corresponding value of 1 in the matrix 'sig'? So for example, in the ggplot2 plot below, the pixel located at [1,3] would be outlined by a black square since the value at sig[1,3] == 1. This is my first
2011 Apr 28
2
changing a specific column name
Hi, Can someone please tell me how to change the column name of a specific column. How do I change the name of the column 'Species'? Thanks in advance d <- iris colnames(d) [1] "Sepal.Length" "Sepal.Width" "Petal.Length" "Petal.Width" "Species" ind <- which(names(d)=='Species') ind [1] 5 colnames(d[ind]) [1]
2008 Jul 27
4
product of successive rows
Hi everyone, I want to perform an operation on a matrx that outputs the product of successive pairs of rows. For example: calculating the product between rows 1 & 2; 3 & 4; 5 & 6...etc. Does anyone know of any readily available functions that can do this? Thanks, rcoder -- View this message in context: http://www.nabble.com/product-of-successive-rows-tp18681259p18681259.html
2003 Feb 10
1
Zero rows/cols in the hessian matrix
Dear R experts! I try to minimize a function with external C fitting function. I get the hessian matrix. Here it is: [,1] [,2] [,3] [,4] [1,] 1.8816631 0 0.8859803 0 [2,] 0.0000000 0 0.0000000 0 [3,] 0.8859803 0 0.4859983 0 [4,] 0.0000000 0 0.0000000 0 Second and fourth rows/columns have zero values only. That's OK, because that ones related
2005 Feb 07
4
proportional matrix rows
Hi I have a two-column integer matrix like this: R> jj [,1] [,2] [1,] -1 1 [2,] -2 2 [3,] -7 6 [4,] -8 7 [5,] -6 5 [6,] -9 8 [7,] -5 4 [8,] 3 -3 [9,] -10 9 [10,] -4 3 I want a diagnostic that detects whether a row is a multiple of the first row or not. In this case, this would be rows 1,2, and 8. How to do this
2013 Jun 10
1
modify and append new rows to a data.frame using ddply
Hi, I have a data.frame that contains a variable act which records the duration (in seconds) of two states (wet-dry) for several individuals (identified by Ring) over a period of time. Since I want to work with daytime (i.e. from sunrise till sunset) and night time (i.e. from sunset till next sunrise), I have to split act from time[i] till sunset and from sunset until time[i+1], and from time[k]
2008 Sep 17
1
Re adout row and column of a matrix value
Hello R users, I want to readout the row and column postion from a certain matrix value into a csv file. I have only found this syntax "which(a == b, arr.ind = T)" so I get a = matrix [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [1,] 1 1 2 2 2 1 1 2 [2,] 1 2 3 3 3 4 4 3 [3,] 3 3 3 5 5 6 5 4 [4,] 4 4 4 3
2012 Apr 06
3
filling the matrix row by row in the order from lower to larger elements
Hello, everybody! I have a matrix "input" (see example below) - with all unique entries that are actually unique ranks (i.e., start with 1, no ties). I want to assign a value of 100 to the first row of the column that contains the minimum (i.e., value of 1). Then, I want to assign a value of 100 to the second row of the column that contains the value of 2, etc. The results I am looking
2013 Jun 08
0
modify and append new rows in a dataframe
My data frame shows changes on the variable act which records the consecutive duration (in seconds) of two states (wet-dry) over a few days for several?individuals (identified by Ring). Since I want to work with daytime (i.e. from dawn till dusk) and night time (i.e. from dusk till next dawn), I have to split act in two: from time[i] till dusk and from dusk until time[i+1], and from time[k] till
2010 Apr 23
3
reordering of matrix rows to maximize the sum of the diagonal
Hi r-help community, This question isn't so much a syntax/coding one, but here goes: Let's say I have matrix of arbitrary dimensions and I'd like to reorder the rows in such a way that I could maximize the sum of the entries along the diagonal. For example, for this 3x3 matrix: [,1] [,2] [,3] [1,] 3 4 13 [2,] 9 1 2 [3,] 2 11 1 rearranging the rows
2010 Sep 06
3
Aggregate certain rows in a matrix
Hi, I have a matrix that looks like this a <- c(1,1,1,1,2,2,3,3,3,3) b <- c(2,2,2,3,4,4,4,5,5,6) c <- c(1,2,3,4,5,6,7,8,9,10) M <- matrix(nr=10,nc=3) M[,1] <- a M[,2] <- b M[,3] <- c > M [,1] [,2] [,3] [1,] 1 2 1 [2,] 1 2 2 [3,] 1 2 3 [4,] 1 3 4 [5,] 2 4 5 [6,] 2 4 6 [7,] 3 4 7
2011 Feb 10
3
Permuting rows of a matrix
Hi, I need to permute the rows of a matrix, where each row is independently rearranged. A simple solution is this: shuffled <- datamatrix <- matrix(1:24, ncol = 4) for (i in 1:nrow(datamatrix)) { shuffled[i, ] <- sample(datamatrix[i, ]) } > datamatrix [,1] [,2] [,3] [,4] [1,] 1 7 13 19 [2,] 2 8 14 20 [3,] 3 9 15 21 [4,] 4 10 16 22 [5,]
2012 May 25
1
Correlograms: using boxes and different variables on rows and columns
I'm trying to make correlograms using corrgram. See below for a simple example. #### library(corrgram) data(baseball) vars1 <- c("Assists","Atbat","Errors","Hits","Homer","logSal") vars2 <- c("Putouts","RBI","Runs","Walks","Years")
2013 Jun 26
3
match rows of R
Hi all, What would be an efficient way to match rows of a matrix to a vector? ex: m<-matrix(1:9, nrow=3) m [,1] [,2] [,3] [1,] 1 4 7 [2,] 2 5 8 [3,] 3 6 9 ################################# which(m==c(2,5,8)) # I want this to return 2 ###################### Thanks, Sachin [[alternative HTML version deleted]]
2018 Feb 28
1
Missed opportunity in the midend, unsigned comparison
Hi everybody, I see a missed optimization opportunity in LLVM that GCC catches and I'd love to hear community's input. Here's the original C code: 1 char arr[2]; 2 char *get(unsigned ind) { 3 if (ind >= 1) { 4 return 0; 5 } 6 return &(arr[ind]); 7 } The variable `ind` is unsigned so, based on the comparison, if it is not greater or equals to one, than it is
2008 Feb 11
4
Conditional rows
Hi, Given a simple example, test <- matrix(c(0.1, 0.2, 0.1, 0.2, 0.1, 0.1, 0.3, 0.1, 0.1), 3, 3) How to generate row indexes for which their corresponding row values are less than or equal to 0.2 ? For this example, row 2 and 3 are the correct ones. Thanks [[alternative HTML version deleted]]
2006 Nov 19
4
The most common row in a matrix?
Hi, How do you get the most common row from a matrix? If I have a matrix like this array(1:3,dim=c(4,5)) [,1] [,2] [,3] [,4] [,5] [1,] 1 2 3 1 2 [2,] 2 3 1 2 3 [3,] 3 1 2 3 1 [4,] 1 2 3 1 2 in which rows 1 and 4 are similar, I want to find that vector c (1,2,3,1,2). Atte Tenkanen University of Turku, Finland