Displaying 20 results from an estimated 3000 matches similar to: "a string to enviroment or function"
2007 Apr 11
5
how to reverse a list
Hi, there:
I am wondering if there is a quick way to "reverse" a list like this:
t0 <- list(a=1, b=1, c=2, d=1)
reverst t0 to t1
> t1
$`1`
[1] "a" "b" "d"
$`2`
[1] "c"
thanks.
--
Weiwei Shi, Ph.D
Research Scientist
GeneGO, Inc.
"Did you always know?"
"No, I did not. But I believed..."
---Matrix III
2007 May 01
1
dlda{supclust} 's output
Hi,
I am using dlda algorithm from supclust package and I am wondering if
the output can be a continuous probability instead of discrete class
label (zero or one) since it puts some restriction on convariance
matrix, compared with lda, while the latter can.
thanks,
--
Weiwei Shi, Ph.D
Research Scientist
GeneGO, Inc.
"Did you always know?"
"No, I did not. But I believed..."
2007 Apr 24
5
intersect more than two sets
Hi,
I searched the archives and did not find a good solution to that.
assume I have 10 sets and I want to have the common character elements of them.
how could i do that?
--
Weiwei Shi, Ph.D
Research Scientist
GeneGO, Inc.
"Did you always know?"
"No, I did not. But I believed..."
---Matrix III
2006 Oct 17
4
cluster in R
hi,
is there some good summary on clustering methods in R? It seems there
are many packages involving it.
And I have two questions on clustering here:
1. Is there a way of evaluate the effecitives (or seperation) of
clustering (rather than by visualization)?
2. Is there a search method (like genetic search) which can help find
the best subset of attributes which gives best seperation?
Thanks,
2008 Aug 24
2
similarity between two gene lists with varied length
Dear listers,
a little off-topic:
I am looking for and compare algorithms which can calculate "distance" or
"similarity" between two gene lists with different lengths.
Any paper, any implementation in R and any suggestion is welcome!
Thanks,
--
Weiwei Shi, Ph.D
Research Scientist
GeneGO, Inc.
"Did you always know?"
"No, I did not. But I believed..."
2007 Oct 29
3
how to split data.frame by row?
hi,
if I have 20 x 3 data.frame, how to split it into
10 x 6 (moving the lower part of 10x3 to column)
or
5 x 12
thanks
--
Weiwei Shi, Ph.D
Research Scientist
GeneGO, Inc.
"Did you always know?"
"No, I did not. But I believed..."
---Matrix III
2007 Jun 25
4
how to plot this?
Hi, there:
Suppose I have a couple of data.frames and each one has five columns
(one for x-axis, two for y-axis and two for std of y's.) There is
another dimensions (besides x and y) which is continuous. My question
is, how to plot such series of data frames in one plot (thus,
3-dimensional plot) AND multiple 2-D plots. I am not familar with R's
plotting utilities.
Thanks.
--
Weiwei
2009 Jul 13
2
how to keep row name if there is only one row selected from a data frame
Hi, there:
Assume I have a dataframe with rownames like A with rownames like a to e,
> A
[,1] [,2]
a 1 6
b 2 7
c 3 8
d 4 9
e 5 10
when I use A[1,], I lost the rowname for it, like below. How could I keep
it? Is there an easy way instead that I have to modify by myself after I
used A[1,] manually.
> A[1,]
[1] 1 6
Thanks,
W.
--
Weiwei Shi, Ph.D
Research
2006 Oct 31
2
how to plot a data.frame?
hi,
i have a data frame like this:
0.3 0.7
0.4 0.8
i am trying to plot this data frame and each cell is filled with
different colors based on the value. Is there a function which can do
this?
thanks,
--
Weiwei Shi, Ph.D
Research Scientist
GeneGO, Inc.
"Did you always know?"
"No, I did not. But I believed..."
---Matrix III
2007 Jun 12
4
pretty report
Dear Listers:
I have a couple of data frames to report and each corresponds to
different condtions, e.g. conditions=c(10, 15, 20, 25). In this
examples, four data frames need to be exported in a "pretty" report.
I knew Perl has some module for exporting data to Excel and after
googling, I found R does not.
So I am wondering if there is a package in R for generating good
reports. I
2007 Jun 18
3
source a specific function
Dear Listers:
For example, if I have a .R source file which has more than one
function, and I want to just load only one of the functions, how could
I do that? (removing the rest after sourcing is not what I intend b/c
in my workspace, I might have some of the rest and I don't want to
change my workspace: i.e., I only change my workspace by adding one
function from a R source file).
Thanks,
2007 Apr 23
6
Random Forest
Hi,
I am trying to print out my confusion matrix after having created my random
forest.
I have put in this command:
fit<-randomForest(MMS_ENABLED_HANDSET~.,data=dat,ntree=500,mtry=14,
na.action=na.omit,confusion=TRUE)
but I can't get it to give me the confusion matrix, anyone know how this
works?
Thansk!
Ruben
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2008 Sep 07
1
cohen's kappa
Dear all,
I have a question on Cohen's kappa:
Assume I have two datasets, one has 500 objects, 10 methods and the other,
1000 different objects, 20 different methods. Could I compare between the
two datasets to conclude the 10 methods are more "concordant" than the 20
ones by looking at some output, for example, cohen.kappa{concord} ?
One more, could anyone explain in brief,
2007 Dec 09
3
editor under MAC system
Dear R-user;
I recently switched from PC to MAC. Is there a compatible editor as
Win-editor with package RWinEdit for MAC?
Thanks
Yihsu Chen
[[alternative HTML version deleted]]
2006 Oct 25
2
write a help file for my own function
Hi,
I am wondering how I can write a help page for my own function so when
I type ?myOwnfunc, then the help page will show up?
thanks.
--
Weiwei Shi, Ph.D
Research Scientist
GeneGO, Inc.
"Did you always know?"
"No, I did not. But I believed..."
---Matrix III
2006 Nov 06
1
colnames and get means for the columns with the "same" names
hi,
I have a conversion table for colnames like this:
Probe_ID HUMAN_LLID
1 AF106325_PROBE1 7052
2 NM_019386_PROBE1 7052
3 NM_012907_PROBE1 339
4 AW917796_PROBE1 84196
5 L27651_PROBE1 10864
The Probe_ID contains a list of colnames for another data.frame, say x1.
I need to convert such colnames to another ID's system, HUMAN_LLID by
using the table.
2006 Oct 18
1
selectively load some objects from old workspace
Dear Listers:
I have a question on loading objects from workspace:
suppose I have two workspaces for two approaches. My old workspace has
some objects I need for the new workspace but I don't want to load the
whole old workspace and remove most of the old objects and get what I
want. Is there an easier way to do like this:
load "some needed obj" from old workspace, which has been
2007 Apr 20
1
simply this loop?
Hi, anyone interested in this:
I tried to simply this loop with lapply or something but haven't figured it out:
mapt = c("203929_s_at", "203930_s_at", "203928_x_at", "206401_s_at")
mapt.combn <- lapply(1:4, function(i) combn(mapt, i))
out = list()
k = 1
for (i in 1:length(mapt.combn)){
for (j in 1:ncol(mapt.combn[[i]])){
out[[k]] =
2007 Aug 28
1
how to calculate mean into a list
Dear Listers:
I have this task and suppose a0 is a list of 10 data.frames, I want to
calculate like this
> (a0[[1]]+a0[[2]]+..+a[[10]])/10
Thanks.
--
Weiwei Shi, Ph.D
Research Scientist
GeneGO, Inc.
"Did you always know?"
"No, I did not. But I believed..."
---Matrix III
2007 Jan 24
3
Cronbach's alpha
Dear Listers:
I used cronbach{psy} to evaluate the internal consistency and some set
of variables gave me alpha=-1.1003, while other, alpha=-0.2;
alpha=0.89; and so on. I am interested in knowing how to interpret
1. negative value
2. negative value less than -1.
I also want to re-mention my previous question about how to evaluate
the consistency of a set of variables and about the total