similar to: locate the rows in a dataframe with some criteria

Hi netters, Suppose I have two data frames X and Y. X has three colnames A, B and C. Y has three colnames A,B and D. I want to combine them into one matrix, joining the rows having the same A and B values (X$A==Y$A and X$B = Y$B). So the resulting dataframe has four variables/columns: A,B,C and D. I was wondering what's the best way to do it in R. Could anyone give me some advice? Thanks!

Hi, netters, First of all, thanks a lot for all the prompt replies to my earlier question about "merging" data frames in R. Actually that's an equivalence to the "join" clause in mysql. Now I have another question. Suppose I have a data frame X with lots of columns/variables: Name, Age,Group, Type, Salary. I wanna do a subtotal of salaries: aggregate(X$Salary,

Dear netters, suppose I have a matrix X [1,] 'c1' 'r6' '150'[2,] 'c1' 'r4' '70'[3,] 'c1' 'r2' '20'[4,] 'c1' 'r5' '90'[5,] 'c2' 'r2' '20'[6,] 'c3' 'r1' '10'I want to apply some funciton to groups of rows by the first column.If the function is just to

Hi netters, I have a matrix X of the size (1000,100). The values are from -3 to +3. When I tried heatmap(X, distfun=function(c),dist(c,method="bin"),hclustfun=function(m),hclust(m,method="average")) I got the error message: Error: evaluation nested too deeply: infinite recursion / options(expressions=)? However, if I used default parameters for distfunction:

Dear all, If I have a data frame x<-data.frame(x1=c(1,7),x2=c(4,6),x3=c(8,2)): x1 x2 x3 1 4 8 7 6 2 I want to sort the whole data and get this: x1 1 x3 2 x2 4 x2 6 x1 7 x3 8 If I do sort(X), R reports: Error in order(list(x1 = c(1, 7), x2 = c(4, 6), x3 = c(8, 2)), decreasing = FALSE) : unimplemented type 'list' in 'orderVector1' The only way

hi netters I have a rather simple question. I have a data frame with two variables X and Y, both of which are factors. X has 100 levels while Y has 10 levels only. The data frame has 100 rows in all, so for X the values are unique, and Y has many replicate values. Now I wanna reduce the data frame into 10 rows only, according to the 10 levels of Y. I don't care which value of X is in

hi netters, suppose i have a series of objects X1, X2, B1,C1........... they all have the same dimensions. i want to combine into one by using cbind: y<-cbind(X1,X2,B1,C1.....) but i don't want to type the names of these objects one by one. instead, i've put their names into a vector: x<-c("X1","X2","B1","C1",....) i used y<-cbind(x).

hi netters Is there a function in R that can compute the quotient and remainder of a division calculation? such that when 11 is given as the dividend and 5 the divider, the function returns 2(quotient) and 1(remainder). Thanks a lot! _________________________________________________________________ 伱佲伔佈佅伮佋佖 MSN Explorer: http://explorer.msn.com/lccn/

hi netters, i have a dataframe A with several columns(variables). the elements of column M are character strings. so A$M=c("ab","abc","bcd","ac","abcd","fg",....."fl"). i wanna extract all the rows where A$M match some regular expression pattern. for a simple example, let the pattern be just "ab", i wanna subset

hi netters, i have a dataframe TEST like this: Y1 Y2 Y3 X1 4 7 8 X2 6 2 Z X3 8 0 1 i would like to change it to a numeric matrix, replacing "Z" with NA Y1 Y2 Y3 X1 4 7 8 X2 6 2 NA X3 8 0 1 i've tried the function data.matrix but it didn't work. is there any easy way to do this? thanks a lot!

hi netters i have a vector NAMES containing a series of variable names: NAMES=c(x,r,z,m,st,qr,.....nn). i wanna fit a regression tree by using the code: my.tree<-tree(y~x+r+z+m+....nn,my.dataframe) but i don't want to type out "x+r+z+m+....+nn" one by one, as there are so many variables. besides, sometimes i wanna put the code in a function. so i need to have the

Hi netters, Now I'm connecting from my local windows machine to a remote linux machine and launch R out there using SSH. When I tried to create grahics, like using plot or heatmap, I cannot see the output. Maybe a new R window displaying the graphics has popped out in the remote machine? Or I need to change some settings for the graphics to display? I don't know. I googled it and

Hi netters, I want to learn a decision tree from a series of instances (learning data). The packages tree or rpart can do this quite well, but the scoring functions (splitting criteria) are fixed in these packages, like gini or something. However, I'm going to use another scoring function. At first I wanna modify the R code of tree or rpart and put my own scoring function in. But it

hi netters Suppose I have a factor X, with 10 elements and 3 levels: A B B C A C B A C C . It is easy to count the number of elements for each level: tapply(X,X,length). Now I have another factor Y, which formed a matrix with X: X| A B B C A C B A C C Y| B B C C C A A A B B I wanna count the number of elements for each of these conditions: when X=A and Y=A; when X=A and Y=B; when X=A and

hi netters, I'm a newbie to R and there are some very simple problems puzzeled me for two days. I've a dataframe here with several columns different in modes. Two of the columns are special for me: column 1 has the mode "factor" and column 2 has the mode "numeric vectors". The values for column 1 are either "T" or "F". I wanna do two things:

Hi netters, I'm using the 64-bit R-2.5.0 on a x86-64 cpu, with an RAM of 2 GB. The operating system is SUSE 10. The system information is: -uname -a Linux someone 2.6.13-15.15-smp #1 SMP Mon Feb 26 14:11:33 UTC 2007 x86_64 x86_64 x86_64 GNU/Linux I used heatmap to process a matrix of the dim [16000,100]. After 3 hours of desperating waiting, R told me: cannot allocate vector of size

Hi netter, Recently I was trying to install rJava. The operating system is suse 10.0, and the R versionis 2.5.0. Following the instructions of R Wiki for rJava, I did configuration first: R CMD javareconf and then it showed a series of information, from what it seems that java is in the system and the configuration succeeded. Then I tried to install rJava:

Hi all I'm trying to install R 2.3.0 under Suse 10.0. As I'm using SSH to login into the SUSE server, I can't use YAST2, so I have to use rpm -i in the shell. The system tells me that I need some other packages such as xorg-x11-fonts-100dpi, blas, libgfortran.so.0(). Is there some website where I can download and install these packages? Thanks a lot! Zhihua Li

Hi, R-users, If I have a data frame like this: >x<-data.frame(g=c("g1","g2","g1","g1","g2"),v=c(1,7,3,2,8)) g v 1 g1 1 2 g2 7 3 g1 3 4 g1 2 5 g2 8 It contains two groups, g1 and g2. Now for each group I want the max v: > aggregate(x$v,list(g=x$g),max) g x 1 g1 3 2 g2 8 Beautiful. But what if I want to keep the row index of (g1

Full_Name: Zhihua Liu Version: 2.6.0 OS: Submission from: (NULL) (66.176.38.107) When I produced a .ps graph in the screen, I had problem to save them. The following warnings show up: Error: Invalid font type In addition: Warning messages: 1: font family not found in PostScript font database 2: font family not found in PostScript font database But it works fine with R 2.5.0.