Displaying 20 results from an estimated 1000 matches similar to: "loop command to matrix"
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
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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 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 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<-
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
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??
2012 Dec 25
2
for loop not working
dear R family,i have a matrix of 444 columns. what i want to do is the following.
1. starting from column 1 i want to select every 37th column on the way. more precisely i want to select column 1, 38,75,112,149 and so on.
2.starting from column 2, i again want to select every 37th column. which means 2,39,76,113,150 and so on.
similarly starting from 3 till 37th column.
i have tried following loop
2012 Oct 15
2
median between matrix column
Dear useRs,
1. how to calculate single median value for two columns of a matrix?
2. i have a matrix of 16 columns and 365 rows, how to calculate median between columns 1 and 16, 2 and 16, 3 and 16, 4 and 16, 5 and 16 till 15th column. is there a loop command to do the said operation?
regards
eliza
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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
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 Mar 06
3
combining column having same values
Dear useRs,
I have a matrix in the following form
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [,11] 1 1 3 2 3 1 1 2 3 3 2
and following is my desired output (combining the column headers, having same values).
a<-1,2,6,7
b<-3,5,9,10
c<-4,8,11
Thanks in advance
Elisa
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2012 Oct 26
3
regression analysis in R
Dear useRs,
i have vectors of about 27 descriptors, each having 703 elements. what i want to do is the following 1. i want to do regression analysis of these 27 vectors individually, against a dependent vector, say B, having same number of elements.2. i would like to know best 10 regression results, if i do regression analysis of dependent vector against the random combination of any 4
2013 Feb 17
6
histogram
HI Elisa,
You could use ?cut()
vec1<-c(33,18,13,47,30,10,6,21,39,25,40,29,14,16,44,1,41,4,15,20,46,32,38,5,31,12,48,27,36,24,34,2,35,11,42,9,8,7,26,22,43,17,19,28,23,3,49,37,50,45)
label1<-unlist(lapply(mapply(c,lapply(seq(0,45,5),function(x) x),lapply(seq(5,50,5),function(x) x),SIMPLIFY=FALSE),function(i) paste(i[1],"<x<=",i[2],sep="")))
2013 Jan 02
4
list of matrices
dear useRs,
i have a list containing 16 matrices. i want to calculate the column mean of each of them.
i tried
>sr <- lapply(s,function(x) colMeans(x, na.rm=TRUE))
but i am getting the following error
>Error in colMeans(x, na.rm = TRUE) : 'x' must be numeric
can it be done in any other way? and why i am getting this error??
thanks in advance..
elisa
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2013 Oct 19
3
bold dot size and name in plot
Dear useRs,
I have the following data "z" of two variables "x"(z[,1]) and "y"(z[,2]).
> dput(z)
structure(c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,
2013 Feb 15
2
data formatting
Dear Eliza,
Try this:
Lines1<-readLines(textConnection("1911.01.01?????? 7.87
1911.01.02?????? 9.26
1911.01.03?????? 8.06
1911.01.04?????? 8.13
1911.01.05????? 12.90
1911.02.06?????? 5.45
1911.02.07?????? 3.26
1911.03.08?????? 5.70
1911.03.09?????? 9.24
1911.04.10?????? 7.60
1911.05.11????? 14.82
1911.05.12????? 14.10
1911.06.13?????? 7.87
1911.06.14?????? 9.26
2013 Jan 11
3
locating element in distance matrix
Dear useRs,
I have a very basic question. I have a distance matrix and i skipped the upper part of it deliberately. The distance matrix is 1000*1000. Then i used "min" command to extract the lowest value from that matrix. Now i want to know what is the location of that lowest element? More precisely, the row and column number of that lowest element.
Thanks in advance
elisa
2013 Feb 17
1
addition in the initial question
Dear Elisa,
Try this:
vec1<-c(33,18,13,47,30,10,6,21,39,25,40,29,14,16,44,1,41,4,15,20,46,32,38,5,31,12,48,27,36,24,34,2,35,11,42,9,8,7,26,22,43,17,19,28,23,3,49,37,50,45)
vec2<-vec1[1:26]
names(vec2)<-LETTERS[1:26]
label1<-unlist(lapply(mapply(c,lapply(seq(0,45,5),function(x) x),lapply(seq(5,50,5),function(x) x),SIMPLIFY=FALSE),function(i)
2012 Dec 24
2
whats wrong in my codes???
Dear R family,i am trying to plot and save, simultaneously, about 1000. the name of each plot is contained in "names" file. when i run this loop, i get an error.
"Error in plot.new() : Unable to open file 'C:/R/SAVEHERE/myplot_Tak.jpg' for writing". could you please correct the mistake in the loop?
>names<-(names(sp))
>for(a in seq_along(names)){
>mypath
2013 Apr 25
2
connecting matrices
Dear Elisa,
Try this:
el<- matrix(1:100,ncol=20)
?set.seed(25)
?el1<- matrix(sample(1:100,20,replace=TRUE),ncol=1)
In the example you showed, there were no column names.?
?list(el[,sort(el1)[1:3]],sort(el1,index.return=TRUE)$ix[1:3])
#[[1]]
?# ?? [,1] [,2] [,3]
#[1,]?? 31?? 61?? 71
#[2,]?? 32?? 62?? 72
#[3,]?? 33?? 63?? 73
#[4,]?? 34?? 64?? 74
#[5,]?? 35?? 65?? 75
#
#[[2]]
#[1] 9 5 3
A.K.