similar to: Vector to Matrix transformation

Displaying 20 results from an estimated 10000 matches similar to: "Vector to Matrix transformation"

2007 Jan 24
3
Conversion of column matrix into a vector without duplicates
Hi R, I have a matrix A, A= [,1] [,2] [1,] a u [2,] b v [3,] c x [4,] d x [5,] e x I want to put the 2nd column of this matrix in a vector without duplicates. i.e., my vector v should be (u, v, x), whose length is 3. Can anybody help me on this? Thanks in advance Shubha. [[alternative HTML version deleted]]
2008 Jul 23
18
Simple... but...
Hi R, If x=c(1,3,5) y=c(2,4,6) I need a vector which is c(1,2,3,4,5,6) from x and y. How do I do it? I mean the best way.... Thanks, Shubha This e-mail may contain confidential and/or privileged i...{{dropped:13}}
2008 May 13
9
A Very Simple Question
On 5/13/2008 10:27 AM, Yukihiro Ishii wrote: > Hi Rusers! > > I am ashed of asking such a simple question. > > X<-matrix(rnorm(24), 4) > X0<-apply(X,2,mean) > > What I want is a matrix which consists of colums such as X[,1]--X0[1]. > > X-X0 doesn't work. > > Perhaps apply function? scale(X, scale=FALSE) ?scale > Thanks in advance. > >
2008 Jun 04
4
sum of unknown number of matrices
Hi R, I have a list of matrices. I need to get the sum of all the matrices in the list. Example: a=b=c=d=matrix(1:4,2,2) l=list(a,b,c,d) I need: > a+b+c+d [,1] [,2] [1,] 4 12 [2,] 8 16 Something like do.call("+",l) is not working...why is this? I may not be knowing the number of matrices in the list... Thanks, Shubha This e-mail
2008 Feb 14
3
Transposing by a group variable
Hi R, Can I transpose a data frame by a particular group variable? For example: d=data.frame(group=c(1,1,2,2,2),val=c(6,4,6,3,5)) And my output should be: data.frame(group=c(1,2),v1=c(6,6),v2=c(4,3),v3=c(NA,5)) Many thanks, Shubha This e-mail may contain confidential and/or privileged i...{{dropped:13}}
2008 May 13
3
Regular Expressions
Hi R, Again struck with regular expressions... Suppose, S=c("World_is_beautiful", "one_two_three_four","My_book") I need to extract the last but one element of the strings. So, my output should look like: Ans=c("is","three","My") gsub() can do this...but wondering how do I give the regular expression....
2008 Jun 09
3
Overlaying the matrices
Hi R, I have a matrix, > x1=matrix(NA,6,6,dimnames=list(letters[1:6],LETTERS[1:6])) > x1 A B C D E F a NA NA NA NA NA NA b NA NA NA NA NA NA c NA NA NA NA NA NA d NA NA NA NA NA NA e NA NA NA NA NA NA f NA NA NA NA NA NA > x2=matrix(rpois(9,1),3,3,dimnames=list(c("b","a","f"),c("D","E","F"))) > x2
2008 Jul 23
8
sequential sum of a vector...
Hi R, Let, x=1:80 I want to sum up first 8 elements of x, then again next 8 elements of x, then again another 8 elements..... So, my new vector should look like: c(36,100,164,228,292,356,420,484,548,612) I used: aggregate(x,list(rep(1:10,each=8)),sum)[-1] or rowsum(x,group=rep(1:10,each=8)) But without grouping, can I achieve the required? Any other ways of doing
2008 Jul 08
8
Sum(Random Numbers)=100
Hi R, I need to generate 50 random numbers (preferably poisson), such that their sum is equal to 100. How do I do this? Thank you, Shubha This e-mail may contain confidential and/or privileged i...{{dropped:13}}
2008 Aug 12
7
Between the values
Hi R, This is a very trivial one.... C=0.1 I want to check whether my value of C is between 0 and 1 exclusively.... I don't want to use (C>0 & C<1). And I can't use a single statement like (0<C<1). Is there a between function? Or how do we specify from 0 to 1? Does %in% help me? Many Thanks, Shubha This e-mail may contain confidential and/or
2008 Apr 09
11
Number of words in a string
Hi R, A quick question: How do we find the number of words in a string? Example: C="Have a nice day" And the number of words should be 4. any built in function or?... Thanks, Shubha Shubha Karanth | Amba Research Ph +91 80 3980 8031 | Mob +91 94 4886 4510 Bangalore * Colombo * London * New York * San José * Singapore * www.ambaresearch.com This e-mail may contain
2008 May 06
2
To preserve the class "Matrix"
Hi, Suppose a=matrix(1:9,3,3) > a [,1] [,2] [,3] [1,] 1 4 7 [2,] 2 5 8 [3,] 3 6 9 Now, > class(a[1:2,]) [1] "matrix" > class(a[1:3,]) [1] "matrix" > class(a[,1:2]) [1] "matrix" > class(a[,1:3]) [1] "matrix" But, > class(a[1,]) [1] "integer" > class(a[,1]) [1]
2007 Feb 13
5
Fatigued R
Hi R, Please solve my problem........... I am extracting Bloomberg data from R, in a loop. R is getting fatigued by doing this process and gives some errors. I introduced sleep function. Doing this sometimes I get the results and sometimes not. I even noticed that if I give complete rest for R (don't open R window) for 1 day and then run my code with the sleep function, then the
2008 Mar 25
3
Dimensions of a List
Hi R, I have a list, l=list(list(c(1,2),c(4,5),c(6,7)),list(c(11,22,33),c(44,55,66))) > l [[1]] [[1]][[1]] [1] 1 2 [[1]][[2]] [1] 4 5 [[1]][[3]] [1] 6 7 [[2]] [[2]][[1]] [1] 11 22 33 [[2]][[2]] [1] 44 55 66 How do I know the dimensions of this list?... In other words, how many sub-lists, sub-sub-lists etc...are there in l? How do I know this?
2006 Nov 16
5
<RBloomberg Package Problem>
Hi R-Experts, I'm currently using R 2.4.0 in Windows XP. I'm trying to download data from Bloomberg using the package "RBloomberg", but it fails to install the three needed packages "zoo", "chron" and 'Rbloomberg". Moreover I am not able to find "RBloomberg" package as windows binary in CRAN site as only for MAC it's given. Please
2010 Jan 03
2
Scores in Dimensions in Correspondence Analysis
Hi R, I was experimenting with the CA package for correspondence analysis. data(author) ca(author) plot(ca(author)) How can I get the values used by the plot for the two axis for biplot? In other words, how will I be able to obtain the scores in the dimensions (which are obtained by PCA) of the graphs? Thanks. Thanks and Regards, Shubha This e-mail may contain
2006 Dec 02
4
Fwd: Urgent Help in Paste Command
Hi Experts, I want to see my object as below: 'C:\Program Files\R\R-2.4.0\bin\Rgui.exe' So I use the paste command. None of the below is working. Could anyone help me on this? > paste("'C:\Program Files\R\R-2.4.0\bin\Rgui.exe'") [1] "'C:Program FilesRR-2.4.0\binRgui.exe'" > paste("'C:","\","Program
2008 May 14
2
dataframes to a list
Hi R, I have the data frames, data1, data2....data50. Now I want to put all of these in a single list. But, >list(data1, data2,.........data50) is very big to write. How do I then do it? Thanks, Shubha This e-mail may contain confidential and/or privileged i...{{dropped:13}}
2008 Aug 07
3
Downloading Yahoo data
Hi R, I am trying to download the data from R. I give the below command. > library(fImport) > yahooSeries("IBM") trying URL 'http://chart.yahoo.com/table.csv?s=IBM&a=7&b=08&c=2007&d=7&e=07&f=2008& g=d&x=.csv' Error in download.file(url = url, destfile = file, method = method) : cannot open URL
2010 Apr 24
4
DICE Coefficient of similarity measure
Hi, I wanted the DICE coefficient (similarity measure for binary variables) to be calculated in R and found that the "igraph" package has the option of "similarity.dice" to do this. But, for this command, the input object should be an igraph object. But, I have a dataframe of columns containing 1's and 0's. Can I convert this dataframe into an igraph object, so that