Displaying 20 results from an estimated 40000 matches similar to: "?mean"
2006 Apr 14
5
vector-factor operation
I found myself wanting to average a vector [vec] within each level of a
factor [Fac], returning a vector of the same length as vec. After a
while I realised that
lm1 <- lm(vec ~ Fac)
fitted(lm1)
did what I want.
But there must be another way to do this, and it would be good to be
able to apply other functions than mean() in this way.
Cheers, Murray
--
Dr Murray Jorgensen
2014 Aug 21
1
Inconsistent handling of data frames in min(), max(), and mean()
This inconsistency recently came to my attention:
> df <- data.frame(A = 1:10, B = rnorm(10))
> min(df)
[1] -1.768958
> max(df)
[1] 10
> mean(df)
[1] NA
Warning message:
In mean.default(df) : argument is not numeric or logical: returning NA
I recall the times where `mean(df)` would give `colMeans(df)` and this
behaviour was deemed inconsistent. It seems though that the change has
2005 May 13
5
Conflict between xtable and Hmisc when using Sweave?
Dear R users,
The Sweave code below runs fine, as it is. However, an error occurs when
the line 'library(xtable)' is uncommented:
Error: chunk 1
Error in "label<-"(`*tmp*`, value = "month") :
no applicable method for "label<-"
Is anybody aware of this and knows a workaround?
Thanks,
Sander.
*******************
2010 Apr 21
5
Bugs? when dealing with contrasts
R version 2.10.1 (2009-12-14)
Copyright (C) 2009 The R Foundation for Statistical Computing
ISBN 3-900051-07-0
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.
Natural language support but running in an English locale
R is a collaborative project with
2011 Jan 19
1
expand.grid
Hello list.
I feel like an idiot.
There exists a method called expand.grid which, from the documentation,
appears to do just what I want, but then it doesn''t, and I can''t get it to
behave.
Given a dataframe
dfr<-data.frame(c1=c("a", "b", NA, "a", "a"), c2=c("d", NA, "d", "e", "e"),
2007 May 18
4
Simple programming question
Hi R-users,
I have a simple question for R heavy users. If I have a data frame like this
dfr <- data.frame(id=1:16, categ=rep(LETTERS[1:4], 4),
var3=c(8,7,6,6,5,4,5,4,3,4,3,2,3,2,1,1))
dfr <- dfr[order(dfr$categ),]
and I want to score values or points in variable named "var3" following this
kind of logic:
1. the highest value of var3 within category (variable named
2007 Jan 28
2
Adding lines to xYplot
I am using xYplot to plot data and CIs. How do I add several lines to
the figure?
_____________________________
Professor Michael Kubovy
University of Virginia
Department of Psychology
USPS: P.O.Box 400400 Charlottesville, VA 22904-4400
Parcels: Room 102 Gilmer Hall
McCormick Road Charlottesville, VA 22903
Office: B011 +1-434-982-4729
Lab: B019
2004 Mar 01
6
How to plot Histogram with frequence overlaid by distribution curve
Hi,
I am facing the problem that I want to plot a histogram chart set
freq to true and overlay with normal or weibull or exponential distribution
curve.
The sample code is shown as below:
>samp<-c(-8.2262,-8.2262,-8.2262,-8.20209,-8.09294,-8.07321,-8.07321,
-8.07321,-8.07175,-8.04948,-8.04948,-8.04948,-8.03848,-8.03848,
2007 Feb 01
2
How can I calculate conditional mean in a large dataset including date data
Dear R users,
I have a dataframe with two columns: first column is date data (e.g.
1/1/2000 with character format: daily data from 1/1/1970 till 31/12/2003)
and second column is temperature value. Now I'd like to calculate mean for
each month in a year (i.e. May 2001, June 1997) and mean for each month in
all of years. As the number of days in some months is different from others
I could
2010 Jul 12
3
How to mean, min lists and numbers
I would like to sum/mean/min a list of lists and numbers to return the
related lists.
-1+2*c(1,1,0)+2+c(-1,10,-1) returns c(2,13,0) but
sum(1,2*c(1,1,0),2,c(-1,10,-1)) returns 15 not a list.
Using the suggestions of Gabor Grothendieck,
Reduce('+',list(-1,2*c(1,1,0),2,c(-1,10,-1))) returns what we want,
c(2,13,0).
However, it seems that this way does not work to mean/min.
So, how to
2010 Aug 11
2
Sweeping a zoo series
Given a long zoo matrix, the goal is to "sweep" out a statistic from the
entire length of the
sequences.
longzoomatrix<-zoo(matrix(rnorm(720),ncol=6),as.yearmon(outer(1900,seq(0,length=120)/12,"+")))
cnames<-c(12345,23456,34567,45678,56789,67890)
colnames(longzoomatrix)<-cnames
longzoomatrix[1:24,]
12345 23456 34567 45678
2024 Sep 08
2
Inconsistency between row and nrow
Hi Gabor,
In strictly reading the help files for both nrow() and row(), the 'x' argument in the former case is "a vector, array, data frame, or NULL.", whereas in the latter case it is "a matrix-like object, that is one with a two-dimensional dim.".
Thus, I would expect row() to fail on a >= 3-dimensional array, as your example shows.
In reading the help file for
2002 Mar 05
3
newbie: remove column with low mean from a matrix
Dear all,
Sorry to bother you with one more newbie question.
I have a dataobject with several hundreds of columns. I want to remove
columns with a mean of the column values below a certain value:
> a<- c(1,2,3,4,5,6)
> b<-c(2,4,6,8,10,12)
> c<- c(3,6,9,12,15,18)
> test<- as.matrix(cbind(a, b, c))
> mean(a)
[1] 3.5
> mean(b)
[1] 7
> mean(c)
[1] 10.5
Say the
2007 Jan 01
3
Wish list
This is my 2007 New Year wishlist for R features:
1. Matrix Multiplication
Enhance matrix multiplication to work with multidimensional
arrays such that the last dimension of the first multiplicand
must equal the first dimension of the second. See:
https://www.stat.math.ethz.ch/pipermail/r-devel/2006-July/038497.html
2. Grid
- logical-valued function as first arg of grid.edit
-
2004 Jul 16
3
sas to r
I would be incredibly grateful to anyone who'll help me translate some
SAS code into R code.
Say for example that I have a dataset named "dat1" that includes five
variables: wshed, site, species, bda, and sla. I can calculate with the
following SAS code the mean, CV, se, and number of observations of
"bda" and "sla" for each combination of
2007 Sep 19
3
delayedAssign
The last two lines of example(delayedAssign) give this:
> e <- (function(x, y = 1, z) environment())(1+2, "y", {cat(" HO! "); pi+2})
> (le <- as.list(e)) # evaluates the promises
$x
<promise: 0x032b31f8>
$y
<promise: 0x032b3230>
$z
<promise: 0x032b3268>
which contrary to the comment appears unevaluated. Is the comment
wrong or is it supposed to
2018 Jul 29
2
odd behavior of names
The first component name has backticks around it and the second does
not. Though not wrong, it seems inconsistent.
list(a = 1, b = 2)
## $`a`
## [1] 1
##
## $b
## [1] 2
R.version.string
## [1] "R version 3.5.1 Patched (2018-07-02 r74950)"
--
Statistics & Software Consulting
GKX Group, GKX Associates Inc.
tel: 1-877-GKX-GROUP
email: ggrothendieck at gmail.com
2024 Sep 08
1
Inconsistency between row and nrow
The fact that it is consistent with the documentation is not the
point. The point is that the design itself is inconsistent.
On Sun, Sep 8, 2024 at 8:27?AM Marc Schwartz <marc_schwartz at me.com> wrote:
>
> Hi Gabor,
>
> In strictly reading the help files for both nrow() and row(), the 'x' argument in the former case is "a vector, array, data frame, or
2004 Jun 14
5
terminology for frames and environments
In ?exists it says:
inherits: should the enclosing frames of the environment be searched?
I believe what it is saying is that if inherits is TRUE and it fails
to find the variable it will look in the parent environment and
the parent of the parent, etc. (as opposed to looking in the calling
frame next and the caller of the caller, etc.)
Now I thought that standard terminology in R was:
1.
2006 Apr 07
3
strange matrix behaviour: is there a matrix with one row?
Consider this:
> y <- matrix(1:8, ncol=2)
> is.matrix(y[-c(1,2),])
[1] TRUE
> is.matrix(y[-c(1,2,3),])
[1] FALSE
> is.matrix(y[-c(1,2,3,4),])
[1] TRUE
It seems like an inconsistent behaviour:
- with 2 or more rows we have a matrix
- with 1 row we do not have a matrix and
- with 0 rows we have a matrix again
I just stumbled on this behaviour, because I had a problem
with my