Displaying 20 results from an estimated 10000 matches similar to: "adding total row/column to table-command"
2008 Apr 01
2
using a variable in a subset of a dataframe
Dear R community, I am using a dataset and would like to define new
variables using a R variable:
e.g.
for (i in 1:10){
dataset$i<-something
}
But this is not the right way, I get only one variable in "dataset"...
How can I change this?
Thank you!
Georg.
************************
Georg Ehret
Johns Hopkins
Baltimore, MD
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2007 Nov 26
3
determine the number of digits printed into graph with "text(...)"
Dear R comunity,
I am printing a number in a graph using "text(...)" - see code
below: "fraction" is my number. I wish to print only two digits of the
number and struggle to do this... options(digit=3) does not work...
Thank you for your suggestions! Cheers, Georg.
**********************************
Georg Ehret
Johns Hopkins
Baltimore
2008 Jun 26
2
density and jpeg
Dear R community, I am using densityplot (lattice package) for a large
dataset and wish to print it to a jpeg (the pdf is huge). R crashes
consistently. Am I doing it wrong or is densityplot incompatible with jpeg?
I work on a Mac, R 2.7.0.
> require(lattice)
> jpeg("test.jpeg")
> d[1:10]
[1] 0.700218 0.700175 0.700357 0.700847 0.698286 0.701520 0.698158 0.699300
0.698819
2008 Apr 15
4
heavy graphs
Dear R community, I am creating large graphs with hundreds of
thousands of datapoints. My usual way for output was pdf, but now I am
getting file sizes of >30Mb that do not open well (or at all) in Adobe. Is
there a way to reduce the resolution or get rid of overlaying datapoints?
Any other idea is also warmly welcome!
Thank you and wishing you a good day!
Georg.
**********************
2008 Jun 30
2
lm and NA
Dear R community, Can I please get some advice on the following: I wish
to obtain a list of residuals, padded by NAs for NAs in my source data. I
tried several options of "na.action", but did not succeed...
Example: I would like to get "0,0,0,0,NA,NA":
> a
[1] 1 2 3 4 NA 9
> b
[1] 3 4 5 6 7 NA
> lm(a~b)$residuals
1 2 3 4
0 0 0 0
>
2008 Jul 11
3
number of effective tests
Dear R community,
I am using 6 variables to test for an effect (by linear regression).
These 6 variables are strongly correlated among each other and I would like
to find out the number of independent test that I perform in this
calcuation. For this I calculated a matrix of correlation coefficients
between the variables (see below). But to find the rank of the table in R is
not the right
2007 Jul 02
2
basics: changing the directory
Dear Ms. R,
I struggle with a very basic command for most of you: How to change the
working-directory by command-line?
Thank you!
Georg.
******************
Georg Ehret
Johns Hopkins University School of Medicine
Broadway Research Building, Room 572
733 N. Broadway
Baltimore, MD 21205
Phone: (410) 502-7530
Fax: (410) 502-7544
e-mail: georg@jhmi.edu
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2009 Oct 28
2
regression on large file
Dear R community,
I have a fairly large file with variables in rows. Every variable
(thousands) needs to be regressed on a reference variable. The file is too
big to load into R (or R gets too slow having done it) and I do now read in
line by line with "scan" (see below) and write the results to out. Although
improved, this is still very slow... Can someone please help me and suggest
2008 May 04
2
plotting pie-charts into a coordinate system
Dear R user group,
I wish to plot small pie-charts to specific coordinates in a e.g.
scatter-plot:
E.g.:
> plot(rnorm(100),rnorm(100))
> points(1,1,col="red",cex=4)
-> I wish to put pie(c(2,3)) at the position of the red circle...
How can I do this efficiently?
Thanking you and wishing you a wonderful Sunday!
Georg.
**************************
Georg Ehret
Johns Hopkins
2008 Apr 30
2
boxplots
Dear R user group,
I am working with boxplots and cannot solve the following problem:
> data<-c(0,15,0,60,0,0,0,0,0,60,60,0,60,0,30,0)
> data
[1] 0 15 0 60 0 0 0 0 0 60 60 0 60 0 30 0
> boxplot(data)
The boxplot has the first hinge and the mean-bar both at 0... Why is this
the mean is clearly >0!
Thanking you and wishing you an excellent day,
Georg.
2010 Jun 07
2
graphical representation of a correlation between 3 variables (~30 datapoints)
Dear Ms and Mr R,
I am seeking a visually appealing presentation of 3 variables (~30
datapoints) that are correlated and that should to into the same direction.
The objective is to show that they do go in the same direction and what
differences there might be while also giving an idea of the values of the
variables. I had done this with simple bargraphs for 6 datapoints in the
past, but for
2008 Apr 02
2
including a variable in another variable name
Dear R community, I wish to include a variable (e.g. slice of "a" below)
in another variable's name. My objective would be to get a variable-name
"data_A" and so on. How can I do this?
> a<-LETTERS[1:25]
> a
[1] "A" "B" "C" "D" "E" "F" "G" "H" "I" "J"
2008 Feb 29
2
printing tables to a pdf
Dear R community,
I wish to print tables into a pdf file. How can this be done, adding
headers and several tables to the same file?
Thanking you for your attention,
Georg.
*****************************
Georg Ehret
Johns Hopkins
Baltimore - US
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2008 Apr 06
1
basics on dataframes
Dear R community,
I am using a dataframe with lots of NAs and wish to create subsets from
that dataframe. In the example below I intend to create a subset with all
entries with V1>1. To my surprise the result also contains all entries with
V1=NA. I would wish to learn more why this is or what I do wrong. I know
that I can use the command "subset" and the NAs will not appear, but
2009 Sep 20
4
running many different regressions
Dear R community,
I have a dataframe with say 100 different variables. I wish to regress
variable 1 separately on every other variable (2-100) in a linear regression
using lm. There must be an easy way to do this without loops, but I have
difficulties figuring this out... Can you please help?
Thank you and best regards, Georg.
*****************************************
Georg Ehret
Johns Hopkins
2007 Oct 10
4
simple function with if -> lapply to dataframe
Dear R,
I am writing a simple function to extract the sign of values and apply it
to a data frame (see below). Whatever I do I get error-messages... What is
wrong?
Thanking you in advance,
Cheers, Georg.
***********************
Georg Ehret
Institute of Genetic Medicine
Johns Hopkins University
Baltimore
> extractsign<-function(x){
+ if (x<0) a<--1
+ else
2008 Apr 22
1
levels in dataframes
Dear R community, I wish to ask a short question concerning factor-data
in dataframes: When I subset the data and get rid of all data for one level,
I still retain the level name (obtained by levels(dataframe$variablename) ).
Is there a convenient way to get rid of the levels for which all data has
been deleted?
Thank you and wishing you an excellent day!
Georg.
2008 Apr 23
1
combining two (or more) tables by creating another dimension
Dear R community, I wish to combine two tables in one by adding an
additional dimension:
e.g.:
>
t1<-as.table(matrix(rnorm(40),nrow=4,ncol=10));rownames(t1)<-c("rowone","rowtwo","rowthree","rowfour")
> t1
A B C D E
F G H I J
rowone
2008 Jan 07
3
two graphs
Dear R community,
I am plotting a histogram and would wish to display another variable of
the same dataset in a very narrow heatmap just below the x-axis. Never mind
the specifics of my task: How can I draw a second graph/image just below a
first graph/image?
Thank you!
Georg.
***************
Georg Ehret
JHU
Baltimore, MD 21043, USA
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2008 May 05
2
splitting a vector on comma
Dear R Usergroup,
I have the following vector and I would like to split it on ",".
How can I do this?
> u
[1]
"160798191,160802762,160813395,160816017,160817873,160824082,160825247,160826925,160834272,160836257,"
Thank you in advance!
With my best regards, Georg.
************************************
Georg Ehret
Baltimore
USA
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