search for: jayuan2008

Displaying 20 results from an estimated 23 matches for "jayuan2008".

2008 Aug 31
3
remove low frequent rows
Hi,   I have a matrix. >a<-cbind(c("a","b","a"),c(4,3,6))      [,1] [,2] [1,] "a"  "4" [2,] "b"  "3" [3,] "a"  "6" I want to remove rows in matrix a whose first column has frequency less than 2. in about example matrix a becomes      [,1] [,2] [1,] "a"  "4" [2,] "a" 
2010 Dec 03
3
colname refered by a variable
Hello,   I tried to use a variable to refer colname, but I got error, could anyone give me advice?   >df=data.frame(cbind(AB=1:3,AC=3:5)) > df$AC [1] 3 4 5 > df$paste("A","C",sep="") Error: attempt to apply non-function thanks Jian   [[alternative HTML version deleted]]
2010 Jun 14
2
list matching
Hello,   I could not find a clear solution for the follow question. please allow me to ask. thanks   mynames=cbind(c('a','b'),c(11,22)) lst=list(a=c(1,2), b=5) now I try to combine mynames and lst: a  1  11   a  2  11 b  5  22   thanks jian   [[alternative HTML version deleted]]
2008 Aug 30
4
remove levels from a factor
Hi,   how to remove levels that have less than a specific number such as 2. i.e..   > f<-as.factor(c("a","b","a")) > f [1] a b a Levels: a b I want to remove level b because level b has less than 2. > f [1] a a Levels: a   [[alternative HTML version deleted]]
2010 Sep 11
5
for loop
Hello, I have a simple question: I want to list numbers 1:k, but if k <1, I hope nothing listed. how should we do? k=2 for (i in 1:k)  print(i) [1] 1    # <-correct [1] 2 k=0 for (i in 1:k) print(i) [1] 1      #<---- wrong [1] 0   thanks jian [[alternative HTML version deleted]]
2010 May 20
5
sort a data.frame
Hello,   I have a dataframe: dd <- data.frame(b = c("chr2", "chr1", "chr15", "chr13"),         x = c("A", "D", "A", "C"), y = c(8, 3, 9, 9),         z = c(1, 1, 1, 2))   >dd       b x y z 1  chr2 A 8 1 2  chr1 D 3 1 3 chr15 A 9 1 4 chr13 C 9 2 Now I want to sort them according column "b", but only its
2010 Jun 07
1
average two sets of columns
Hi R experts. how can I average two sets of columns? dd <- data.frame(b = c("chr2", "chr1", "chrY", "chr13", "chrX"),         w=11:15, x = 1:5, y = c(8, 3, 9, 9,7),        z = c(1, 1, 1, 2, 8)) expected result for mean(w,x) and mean(y,z) is 1  chr2 6  4.5 2  chr1 7  2 3  chrY 8  5 4 chr13 9  5.5 5  chrX 10 7.5 Yu [[alternative
2010 Apr 29
2
by funtion
Hello, I have a data.frame: name    col1    col2    col3    col4 AA    23    54    0.999    0.78 BB    123    5    1    0.99 AA    203    98    0.79    0.99 I want to get mean value data.frame in terms of name: name    col1    col2    col3    col4 AA    113.0000  76.0000   0.8945   0.8850 BB    123.00   5.00   1.00   0.99 I tried to use by function: >aa<-by(test[,2:5], feature, mean)
2010 May 11
1
create a data.frame for aov
Hi R-experts, I try to find a way to transfer a matrix to a data.frame that is used as input of aov. can you give me advice for that? >mdat <- matrix(c(1,2,3, 11,12,13), nrow = 2, ncol=3, byrow=TRUE, dimnames = list(c("row1", "row2"), c("Col1", "Col2", "Col3"))) >mdat      Col1 Col2 Col3 row1    1    2    3 row2   11   12   13 ===>
2010 May 12
3
intersect
Hi there, how can I test every element in a vector whether appears in another vector? such as a<-c("aa", "bb", "ff", "cc") b <-c("oo","jj","bb","cc") somefunction(a,b) gives [False, True, False, True] thanks yuan jian [[alternative HTML version deleted]]
2010 May 13
1
merge for data.frame and matrix
Hello, how to merge a data.frame and a matrix by one column in the data.frame and rownames of the matrix? df <- data.frame(col1=c("kk","yy","kk"),col2=c(6,4,3)) > df   col1 col2 1   kk    6 2   yy    4 3   kk    3 m<-matrix(c(3,8,56,9), nrow=2, dimnames = list(c("aa","kk"),c("col1","col2"))) > m    col1 col2 aa   
2008 Feb 23
2
.net and R
Hi, is it possible to call R functions from visual studio .net such as c#? --------------------------------- [[alternative HTML version deleted]]
2010 May 10
1
how to get p-value from ave
Hi there, I checked google for aov. usually one uses summary to see whether the p-value is small. but I want to put aov in my script. how can I get the p-value, (0.1115, 0.6665, 0.6665 in the following example)? thanks YU > datafilename="http://personality-project.org/r/datasets/R.appendix2.data" > data.example2=read.table(datafilename,header=T) > aov.ex2 =
2010 Jun 02
3
charactor matrix convert to numeric matrix
Hello R experts, can you tell me a simple way to convert a charactor matrix to numeric matrix? if I use as.numeric, the matrix is converted to a vector. a<-cbind(c("23","54","65"),c("1","2","3")) a      [,1] [,2] [1,] "23" "1" [2,] "54" "2" [3,] "65" "3"  as.numeric(a)
2010 Sep 22
3
merge verctor and matrix
hi, can anyone tell me how to merge a vector and a matrix? > v=c(1,4,2) > names(v)=c("e","r","t") > m=matrix(c("r","t","r","s","e",5,6,7,8,9),nr=5) > colnames(m)=c("c1","c2") I want to do like merge(v, m, by.x="names",by.y="c1") I got error Error in fix.by(by.x, x) :
2010 May 21
3
vaiable in lm
Hi, if I know the colnames x and y in the following example, I can easily to do lm. tmp <- data.frame(x=c(1,1.2),y=c(1,2)) lm(y ~ x, data=tmp) when the colnames are variable, what should I do? for example colnames(tmp)[1] <- paste("aa",1,sep="_") lm(y ~ paste("aa",1,sep="_"), data = tmp) it gives me error. [[alternative HTML version
2010 Jun 23
4
list operation
Hi,   it seems a simple problem, but I can not find a clear way. I have a list: lst=list(m=c('a','b','c'),n=c('c','a'),l=c('a','bc')) > lst $m [1] "a" "b" "c" $n [1] "c" "a" $l [1] "a"  "bc" how can I get list elements that include a given subset? for example, for given
2008 Aug 31
4
give all combinations
Hello,   is there a simple way to give all combinations for a given vector:   v<-c("a","b","c")   combination(v,v) becomes "aa","ab","ac","bb","bc","cc'   combination(v,v,v) becomes "aaa","aab","aac","abb",......     [[alternative HTML version deleted]]
2011 Jan 12
2
plot: skip a range of axis
Hi, I am using plot to show scatter points in 2_D. in my data, there is no data between -1 and +1 in x-axis. I want to skip this region, i.e. x axis becomes [-Inf:-1, 1:Inf]. can any one tell me how to do? YU [[alternative HTML version deleted]]
2008 Aug 25
1
cbind in data.frame
hi, when I used cbind to combine columns, some contents of columns has been replaced by number. in the script below, column should be aaa,bbb,ccc but I was given 1,2,3. but when I change the column to vector, it gave me correct contents. can you please tell me why?   > d<-read.table("aaa.txt") > d    V1  V2 1 aaa 123 2 bbb 345 3 ccc 986 > cbind(d[,1],d[,2])      [,1] [,2]