Displaying 20 results from an estimated 8000 matches similar to: "data manipulation between vector and matrix"
2013 Jan 10
1
merging command
HI Eliza,
You could do this:
set.seed(15)
mat1<-matrix(sample(1:800,124*12,replace=TRUE),nrow=12) # smaller dataset
#Your codes
?list1<-list()
?for(i in 1:ncol(mat1)){
? list1[[i]]<-t(apply(mat1,1,function(x) x[i]-x))
? list1}
?x<-list1??
x<-matrix(unlist(x),nrow=12)
x<-abs(x)
?y<-colSums(x, na.rm=FALSE)
z<-matrix(y,ncol=10)
?z<-as.dist(z)
?z
?# ?? 1?? 2?? 3?? 4?? 5??
2013 Sep 02
3
Product of certain rows in a matrix
Hi,
You could try:
A<- matrix(unlist(read.table(text="
1 2 3
4 5 6
7 8 9
9 8 7
6 5 4
3 2 1
",sep="",header=FALSE)),ncol=3,byrow=FALSE,dimnames=NULL)
library(matrixStats)
?res1<-t(sapply(split(as.data.frame(A),as.numeric(gl(nrow(A),2,6))),colProds))
?res1
#? [,1] [,2] [,3]
#1??? 4?? 10?? 18
#2?? 63?? 64?? 63
#3?? 18?? 10??? 4
2012 Oct 05
3
loop for column substraction of a matrix
Dear useRs,
I have a matrix with 38 columns and 365 rows. what i want to do is the following.....
1. subtracting from each column, first itself and then all the remaining columns. More precisely, from column number 1, i will first subtract itself(column 1) and then the remaining 37 columns. Afterwards i will take column number 2 and do the same. In this way i want to proceed till 38th column.
2013 Apr 12
2
processing matrix equation derived from rows of two matrices
Hi,
May be this helps:
?tb[1,]%*%(((val-rep(meansb79[1,],5))^2)/6)
#??????? [,1]
#[1,] 1.47619
tryvarb<-c(1,2,3,4,4,4,4)
?var(tryvarb)
#[1] 1.47619
tb[2,]%*%(((val-rep(meansb79[2,],5))^2)/6)
#???????? [,1]
#[1,] 1.904762
sapply(seq_len(nrow(tb)),function(i) tb[i,]%*%(((val-rep(meansb79[i,],5))^2/6)))
# [1] 1.4761905 1.9047619 1.9047619 1.9047619 1.9047619 2.2857143 1.9047619
# [8] 1.9047619
2013 Sep 27
3
Compare species presence and absence between sites
Dear List,
I want to compare the presence and absence of bird species based on the
sites in a matrix.
The matrix has 5 rows for Island A, B, C, D, and E.
It has 100 columns for bird species D001-D100.
In each cell of the matrix,
the presence-absence of bird species will be recorded as 1 or 0.
(For example, if species D001 is found on Island D,
the matrix cell of species D001 and Island D
2013 Feb 13
3
date and matrices
Hi Elisa,
Try this:
date1<-format(seq.Date(as.Date("1991.1.1",format="%Y.%m.%d"),as.Date("1996.12.31",format="%Y.%m.%d"),by="day"),"%Y.%m.%d")
?length(date1)
#[1] 2192
mat1<-matrix(c(.314,.314,.273,.273,.236,.236,.236,.236,.273,.314,.403,.314),ncol=1)
res1<-
2012 Nov 16
4
Deleting rows with special character
Dear all,
maybe a simple problem but I found no solution for my problem.
I have a matrix Y with 23 000 rows and 220 colums. The entries are "A", "B" or "C".
I want to extract all rows (as a matrix ) of the matrix Y where all entries of a row are (for example) "A".
Is there any solution? I tried the stringr- package but i doesn't work out.
All the best
2006 Aug 28
2
Cannot get simple data.frame binding.
I am stuck on a simple problem where an example works
fine but the real one does not.
I have a data.frame where I wish to sum up some values
across the rows and create a new data.frame with some
of old data.frame variables and the new summed
variable.
It works fine in my simple example but I am doing
something wrong in the real world. In the real world
I am loading a labeled data.frame. The
2013 Apr 15
3
Indices of lowest values in matrix
Dear R users,Sorry for such a basic question. I really need to know that how can i pick the indices of 5 lowest values from each row of a matrix with dimensions 12*12??Thank you very much in advance
Elisa
[[alternative HTML version deleted]]
2013 Feb 19
1
data format
Hi,
Try this:
el<- read.csv("el.csv",header=TRUE,sep="\t",stringsAsFactors=FALSE)
?elsplit<- split(el,el$st)
?
datetrial<-data.frame(date1=seq.Date(as.Date("1930.1.1",format="%Y.%m.%d"),as.Date("2010.12.31",format="%Y.%m.%d"),by="day"))
elsplit1<- lapply(elsplit,function(x)
2013 Mar 18
4
Counting confidence intervals
Hi,
I have a 2 x 10000 matrix of confidence intervals. The first column is the
lower and the next column is the upper. I want to cont how many times a
number say 12 lies in the interval. Can anyone assist?
--
Thanks,
Jim.
[[alternative HTML version deleted]]
2012 Nov 27
3
loop command to matrix
Dear UseRs,Extremely sorry for a basic question. I have a matrix of 19 rows and 365 columns. what i want to do is the following...First i want to leave out column number 1 and want to calculate the row wise mean of the remaining columns, which will obviously give me 365 values in one column, and then subtracting these values from the column i left out i.e. col=1 then i want to leave out column 2
2013 Sep 20
3
search species with all absence in a presence-absence matrix
Dear list
I have a matrix composed of islandID as rows and speciesID as columns.
IslandID: Island A, B, C….O (15 islands in total)
SpeciesID: D0001, D0002, D0003….D0100 (100 species in total)
The cell of the matrix describes presence (1) or absence (0) of the species
in an island.
Now I would like to search the species with absence (0)
in all the islands (Island A to Island O.)
2012 Dec 12
1
Subset of Data
Hi Arun,
I have a question about choosing a subset of data.
I have a matrix of 5000 in 3500.
I want to choose specific variables such as proc1 to proc1000 and Lab1 to Lab1600 and put it into a new matrix to run some correlation analysis.
Since I have 3500 variables, I don't know from what column my lab or procedures start.
I really appreciate your help.
Thanks.
Best,Farnoosh Sheikhi
2013 Apr 10
6
means in tables
Hi.
I have 2 tables, with same dimensions (8000 x 5). Something like:
tab1:
V1 V2 V3 V4 V5
14.23 1.71 2.43 15.6 127
13.20 1.78 2.14 11.2 100
13.16 2.36 2.67 18.6 101
14.37 1.95 2.50 16.8 113
13.24 2.59 2.87 21.0 118
tab2:
V1 V2 V3 V4 V5
1.23 1.1 2.3 1.6 17
1.20 1.8 2.4 1.2 10
1.16 2.6 2.7 1.6 11
1.37 1.5 2.0 1.8 13
1.24 2.9 2.7 2.0 18
I need generate a table of averages, the
2013 Feb 27
2
matrix multiplication
Hi,
Try this:
#mat1 is the data
res<-do.call(cbind,lapply(seq_len(nrow(mat1)),function(i) {new1<-do.call(rbind,lapply(seq_len(nrow(mat1[-i,])),function(j) {x1<-rbind(mat1[i,],mat1[j,]); x2<-(abs(x1[1,1]-x1[2,1])*abs(x1[1,5]-x1[2,5]))+(abs(x1[1,2]-x1[2,2])*abs(x1[1,6]-x1[2,6]))+(abs(x1[1,3]-x1[2,3])*abs(x1[1,7]-x1[2,7]))+(abs(x1[1,4]-x1[2,4])*abs(x1[1,8]-x1[2,8]))}));new1}))
2013 Apr 24
2
Distance matrices Combinations
Dear UseRs,
MY PROBLEM IS A SMALL PIECE OF A REAL BIG AND A COMPLICATED PROBLEM. IF I DELIBERATE IN A VERY SIMPLE WAY THEN ALL I
WANT IS TO PUT ALL THE POSSIBLE COMBINATIONS OF 75 DISTANCE MATRICES (BY TAKING 4 MATRICES, MORE COMMONLY 75C4), in the following equation.
t<-as.matrix((MAT1)^2+(MAT2)^2+(MAT3)^2+(MAT4)^2+,upper=T,diag=T))
Then "1215450" values of "t"(one for
2011 Aug 04
1
matrix rows to single numeric element
I have a matrix of 5 columns and 64 rows, let's call it "mat1". All values are 1 or 0. I need to take the values of the elements by row and create a single numeric element that can be placed its respective slot in a 64-element list, named "list1". For example, mat1[11,1:5] = 0,1,1,0,1 and I must put 01101, with a length of 1, into the 11th element of list1. I can create
2013 Jan 03
5
splitting matrices
Dear useRs,
i want to split a matrix having 1116rows and 12 columns. i want to split that matrix into 36 small matrices each having 12 columns and 31 rows. The big matrix should be splitted row wise. which means that the first small matrix should copy values which are in first 31 rows and 12 columns of the big matrix. similarly 2nd small matrix should contain values from 32nd to 63rd row of the
2011 Nov 27
1
generating a vector of y_t = \sum_{i = 1}^t (alpha^i * x_{t - i + 1})
Dear R-help,
I have been trying really hard to generate the following vector given
the data (x) and parameter (alpha) efficiently.
Let y be the output list, the aim is to produce the the following
vector(y) with at least half the time used by the loop example below.
y[1] = alpha * x[1]
y[2] = alpha^2 * x[1] + alpha * x[2]
y[3] = alpha^3 * x[1] + alpha^2 * x[2] + alpha * x[3]
.....
below are