Displaying 20 results from an estimated 3165 matches for "medicinal".
2009 Dec 03
3
data manipulation
Dear Wiza[R]ds,
I have a data.frame header that looks like this:
v2FfaPre15 v2FfaPre10 v2FfaPre5 v2Ffa2 v2Ffa3 v2Ffa4
I need it to look like this,
15 10 5 2 3 4
i.e., with v2FfaPre and v2Ffa stripped off
Any suggestions,
Thanks in advance!
--
Oscar
Oscar A. Linares, MD
Translational Medicine Unit
LaPlaisance Bay, Bolles Harbor
Monroe, Michigan 48161
2016 Apr 07
0
using apply to a data frame
??I would like to apply a function, fract, to the columns of a
dataframe. I tried the following
apply(data5NonEventEpochs,2,fract)
but, no surprise it did not work as apply works on matrices not data
frames. How can I apply a fuction to the columns of a data frame? (I
can't covert data5NonEventsEpochs to a matrix as it contains character
data).
Thank you,
John
John David Sorkin M.D., Ph.D.
2010 Jan 06
1
boxplot help
Dear Rexperts,
I am trying to add a '+' identifying the mean in a boxplot using the
following
sizelist <- split(size, grp)
centers <- boxplot(sizelist, style.bxp = "att", medpch = "o",
ylab = "Prostate Volume (cm3)")
points(centers, unlist(lapply(sizelist, mean)), pch = "+")
But, I get error
Error in xy.coords(x, y) :
2009 Dec 07
1
anova/factor
Dear Wiza[R]ds,
I have the following data in a data.frame. I need to do an anova with
multiple comparison but I don't know how to factor the groups for analysis.
There are 3 groups, 1,2 and 3 labelled in column 1. Help appreciated with
thanks in advance.
Group SI Sif SG Io I2 lol2
1 9.08e-05 9.08e+00 0.060842287 1.798556446 32.574500
2009 Nov 29
3
Plotting observed vs. Predicted values, change of symbols
Dear Wiz[R]ds,
I am deeply grateful for the help from Duncan Murdoch, Gray Calhoun, and
others. We are almost there. For whatever reason, I can't change the symbol
from a circle to a triangle in the upright posture plots. Any ideas? I have
included the problem in full.
# tritiated (3H)-Norepinephrine(NE) disappearance from plasma
# concentrations supine and upright
# supine
datasu <-
2023 Dec 07
4
Convert character date time to R date-time variable.
Colleagues,
I have a matrix of character data that represents date and time. The format of each element of the matrix is
"2020-09-17_00:00:00"
How can I convert the elements into a valid R date-time constant?
Thank you,
John
John David Sorkin M.D., Ph.D.
Professor of Medicine, University of Maryland School of Medicine;
Associate Director for Biostatistics and Informatics,
2018 Mar 22
3
How do I include a factor in a groupedData object? Meaning and use of inner and outer parameters
Windows 10 64-bit, R-Studio, R version 3.4.3
Several questions relating to groupedData:
(1) I am trying to create a groupedData object that can be used to run an analysis that I have been able to urn using lmer. When I include the interaction terms in the groupedData opbject I get an error message stating that + is not meaningful for factors. How do I include factors in my model? See code and
2017 Oct 23
1
Syntax for fit.contrast (from package gmodels)
David,
predict.glm and se.fit were exactly what I was looking for.
Many thanks!
John
John David Sorkin M.D., Ph.D.
Professor of Medicine
Chief, Biostatistics and Informatics
University of Maryland School of Medicine Division of Gerontology and Geriatric Medicine
Baltimore VA Medical Center
10 North Greene Street
GRECC (BT/18/GR)
Baltimore, MD 21201-1524
(Phone) 410-605-7119
(Fax)
2017 Oct 23
2
Syntax for fit.contrast (from package gmodels)
David,
Again you have my thanks!.
You are correct. What I want is not technically a contrast. What I want is the estimate for "regional" and its SE. I don't mind if I get these on the log scale; I can get the anti-log. Can you suggest how I can get the point estimate and its SE for "regional"? The predict function will give the point estimate, but not (to my knowledge)
2016 Apr 05
2
Specifying path to a windows server
Windows 7 (local computer)
Windows server (server I am trying to reach)
I need to read a file whose windows path is of the form
\\Theserver\mydirectory\data.csv
You will note that as per windows standards the server name is preceded by two backslashes.
I am not sure how to specify this in R. One usually needs to specify an escape characters in a path new which would suggest my path should
2018 Mar 21
3
Mean of a row of a data frame
I am trying to get the mean of a row of a data frame. My code follows:
roop <- data.frame(x=c(1,2,3),y=c(4,5,2),z=c(0,9,4))
roop
mean(roop[1,])
mean(roop[1,c("x","y","z")])
I get the following output:
> roop
x y z
1 1 4 0
2 2 5 9
3 3 2 4
> mean(roop[1,])
[1] NA
Warning message:
In mean.default(roop[1, ]) :
argument is not numeric or logical:
2017 Oct 23
0
Syntax for fit.contrast (from package gmodels)
> On Oct 22, 2017, at 5:01 PM, Sorkin, John <jsorkin at som.umaryland.edu> wrote:
>
> David,
> Again you have my thanks!.
> You are correct. What I want is not technically a contrast. What I want is the estimate for "regional" and its SE.
There needs to be a reference value for the contrast. Contrasts are differences. I gave you the choice of two references
2008 Feb 08
2
R version of SAS Proc Varclus
I am interested in finding an R version of SAS "Proc Varclus". SAS's Proc Varclus implements an oblique cluster analysis based on principal components. How can I find out if R has a package that runs the same algorithm implemented in SAS "Proc Varclus"?
Thank you,
Mary Helen Black
__________________________
Mary Helen Black, M.S.
Keck School of Medicine of USC
2024 Jul 11
1
Issues with Ubuntu 22.04 and Installing the Latest Version of R (R 4.4.1) to Docker Image
Yes, keep the $(lsb-release -cs) there. This allows you to change the version of the OS without having to change anything else (for instance we are migrating all of our docker to 24.04 LTS right now, so we only have to modify the FROM entry and all of our Dockerfile will still work).
From: Gerber, Lauren J <lauren.gerber at helsinki.fi>
Date: Thursday, July 11, 2024 at 2:21?AM
To:
2016 Apr 17
3
Trying to understand cut
Jeff,
Perhaps I was sloppy with my notation:
I want groups
>=0 <10
>=10 <20
>=20<30
......
>=90 <100
In any event, my question remains, why did the four different versions of cut give me the same results? I hope someone can explain to me the function of
include.lowest and right in the call to cut. As demonstrated in my example below, the parameters do not seem to alter
2016 Apr 01
2
p values from GLM
How can I get the p values from a glm ? I want to get the p values so I can add them to a custom report
fitwean<- glm(data[,"JWean"]~data[,"Group"],data=data,family=binomial(link ="logit"))
summary(fitwean) # This lists the coefficeints, SEs, z and p values, but I can't isolate the pvalues.
names(summary(fitwean)) # I see the coefficients,
2020 Oct 06
4
Solving a simple linear equation using uniroot give error object 'x' not found
Colleagues,
I am trying to learn to use uniroot to solve a simple linear equation. I define the function, prove the function and a call to the function works. When I try to use uniroot to solve the equation I get an error message,
Error in yfu n(x,10,20) : object 'x' not found.
I hope someone can tell we how I can fix the problem
2018 Mar 22
0
How do I include a factor in a groupedData object? Meaning and use of inner and outer parameters
Dear John
You are only allowed to have the primary covariate on the left hand side
of the vertical bar. Other covariates go in inner or outer.
Michael
On 22/03/2018 12:59, Sorkin, John wrote:
> Windows 10 64-bit, R-Studio, R version 3.4.3
>
>
> Several questions relating to groupedData:
>
> (1) I am trying to create a groupedData object that can be used to run an analysis
2005 Jul 28
4
CSV file and date. Dates are read as factors!
I am using read.csv to read a CSV file (produced by saving an Excel file
as a CSV file). The columns containing dates are being read as factors.
Because of this, I can not compute follow-up time, i.e.
Followup<-postDate-preDate. I would appreciate any suggestion that would
help me read the dates as dates and thus allow me to calculate follow-up
time.
Thanks
John
John Sorkin M.D., Ph.D.
Chief,
2010 May 02
2
Calculation error
Dear Rxperts,
Running the following code:
=======================================================
twlo=10; twhi=20; wt=154; vd=0.5; cl=0.046; tau=6; t=3; F=1;
wtkg <- wt/2.2 # convert lbs to kg
vd.pt <- wtkg * vd # compute weight-based vd (L)
cl.pt <- wtkg * cl # compute CL (L/hr)
k <- cl.pt/vd.pt # compute k (hr^-1)
cave <-