Displaying 20 results from an estimated 20000 matches similar to: "Bug on r-bc?"
2007 Sep 07
3
Delete query in sqldf?
Dear All,
Is sqldf equipped with delete queries? I have tried delete queries but
with no success.
Thanks in advance,
Paul
2008 Jan 07
7
Can R solve this optimization problem?
Dear All,
I am trying to solve the following maximization problem with R:
find x(t) (continuous) that maximizes the
integral of x(t) with t from 0 to 1,
subject to the constraints
dx/dt = u,
|u| <= 1,
x(0) = x(1) = 0.
The analytical solution can be obtained easily, but I am trying to
understand whether R is able to solve numerically problems like this
one. I have tried to find an
2007 Nov 10
7
How to more efficently read in a big matrix
Dear list,
I need to read in a big table with 487 columns and 238,305 rows (row names
and column names are supplied). Is there a code to read in the table in
a fast way? I tried the read.table() but it seems that it takes forever :(
Thanks a lot!
Best,
Allen
2008 Nov 02
5
R newbie: how to replace string/regular expression
Hello;
I am a R newbie and would like to know correct and efficient method for
doing string replacement.
I have a large data set, where I want to replace character "M", "b",
and "K" (currency in Million, Billion and K) to millions. That is
209.7B with (209.7 * 10e6) and 100.00K with (100.00 *1/100)
and etc..
d <- c("120.0M", "11.01m",
2008 Nov 29
2
Using grep() to subset lines of text
I have two vectors, a and b. b is a text file. I want to find in b those
elements of a which occur at the beginning of the line in b. I have the
following code, but it only returns a value for the first value in a, but I
want both. Any ideas please.
a = c(2,3)
b = NULL
b[1] = "aaa 2 aaa"
b[2] = "2 aaa"
b[3] = "3 aaa"
b[4] = "aaa 3 aaa"
2006 Oct 16
2
New package Ryacas
Ryacas is an R interface to the free yacas computer algebra
system. Ryacas allows one to send R expressions,
unprocessed yacas strings and certain other R objects to a
separate yacas process from R and get back the result. It
also has facilities for manipulating yacas strings and R
expressions destined for yacas processing.
It can be used for exact arithmetic, symbolic math, ASCII
pretty
2006 Oct 16
2
New package Ryacas
Ryacas is an R interface to the free yacas computer algebra
system. Ryacas allows one to send R expressions,
unprocessed yacas strings and certain other R objects to a
separate yacas process from R and get back the result. It
also has facilities for manipulating yacas strings and R
expressions destined for yacas processing.
It can be used for exact arithmetic, symbolic math, ASCII
pretty
2006 Oct 16
2
New package Ryacas
Ryacas is an R interface to the free yacas computer algebra
system. Ryacas allows one to send R expressions,
unprocessed yacas strings and certain other R objects to a
separate yacas process from R and get back the result. It
also has facilities for manipulating yacas strings and R
expressions destined for yacas processing.
It can be used for exact arithmetic, symbolic math, ASCII
pretty
2007 Nov 18
2
Getting theta in italic in a plot
Dear All,
Consider the following code:
plot(0,0)
text(0,0.5,expression(italic(theta)))
I would like to get theta in italic, but I always get it upright. Any
suggestions?
Thanks in advance,
Paul
2007 Nov 13
7
combine two dataframe
I have two data frame A and B adn want to cross them.
A has format as:
a1 a2 a3
1 2 3
2 3 1
1 3 2
...
B:
b1 b2
1 2
2 1
...
the combine result shall be something like
a1 a2 a3 b1 b2
1 2 3 1 2
1 2 3 2 1
2 3 1 1 2
2 3 1 2 1
1 3 2 1 2
1 3 2 2 1
....
is there a function able of doing this instead of loops?
Thanks,
Sun
2008 Jun 14
2
strsplit, keeping delimiters
Hi all,
Does anyone have a version of strsplit that keeps the string that is
split by. e.g. from
x <- "A: 123 B: 456 C: 678"
I'd like to get
c("A:", "123 ", "B: ", "456 ", "C: ", 678)
but
strsplit(x, "[A-Z]+:")
gives me
c("", " 123 ", " 456 ", " 678")
Any ideas?
Thanks,
2008 Oct 03
1
Attributes of top level environments clobbered (was Re: [R] possible bug in function 'var' in R 2.7.2?)
On Fri, Oct 3, 2008 at 3:23 AM, Martin Maechler
<maechler at stat.math.ethz.ch> wrote:
> a much better (and much less error-prone) idea would be to install
> R 2.8.0 alpha even now.
> It will become 'beta' early next week.
>
> We are asking the R community to please install and use
> pre-release versions of R (if you can / are allowed to)
> at least from beta
2013 Apr 20
3
R CMD build
I have no idea where I must R CMD build...
I am using Windows 7 wiht pearl installed
http://stat.ethz.ch/R-manual/R-patched/library/utils/html/PkgUtils.html
its completely unclear for me ... sorry
Knut
2006 Mar 25
7
Regexp subexpression
I can't get the PERL subexpression translated to R. Following, for example,
B. Ripley's
http://finzi.psych.upenn.edu/R/Rhelp02a/archive/58984.html
I am using sub, but it looks like an ugly substitute. Assume I want to
extract the first alpha part and the first numeric part, but only if they
are in sequence.
Do I really have to use the sub twice, first extracting the first variable,
then
2004 Dec 24
6
Sorting problem
Hi
I'm using R 2.0 in SuSE 9.2.
When I plot data as a boxplot, the boxes appear on the plot in
alphabetical order (of group) rather than the order in which they appear
in the data. So far, the only thing I can do to fix this is to prefix
the group labels with a,b,c...etc to trick R into plotting them in the
right order.
Can sorting be turned off?
How should I address this sensibly?
Thanks
2023 Nov 14
1
data.frame weirdness
Also why should that difference result in different behavior?
On Tue, Nov 14, 2023 at 9:38?AM Gabor Grothendieck
<ggrothendieck at gmail.com> wrote:
>
> In that case identical should be FALSE but it is TRUE
>
> identical(a1, a2)
> ## [1] TRUE
>
>
> On Tue, Nov 14, 2023 at 8:58?AM Deepayan Sarkar
> <deepayan.sarkar at gmail.com> wrote:
> >
> >
2006 Nov 23
4
Ryacas and fractions with simultaenously very large numerators and denominators
Dear All
I am doing the following:
> x <- yacas("3/2")
> for (i in 2:400)
+ x <- yacas(paste(x,"*",x))
> x
expression(Inf^1.260864167e+117/Inf^6.304320836e+116)
> Eval(x)
[1] NaN
No luck this way. However, I am successful with
> y <- yacas("(3/2)^400")
> y
expression(7.05507910865533e+190/2.58224987808691e+120)
> Eval(y)
[1]
2004 Mar 18
12
substitute question
Consider the following example:
# substitute a with b in the indicated function. Seems to work.
> z <- substitute( function()a+1, list(a=quote(b)) )
> z
function() b + 1
# z is an object of class call so use eval
# to turn it into an object of class expression; however,
# when z is evaluated, the variable a returns.
> eval(z)
function()a+1
Why did a suddenly reappear again
2018 Jan 25
6
Portable R in zip file for Windows
What is wrong with you guys? I asked for a zip, like R Studio has for
example. Totally clear.
I cant execute exes. But I can unzip files.
Thanks Gabor, I had that in mind, but can't execute the exe due to security
restrictions.
Geez, really, treating people who ask questions this way just makes you
don't want to ask a single one.
On Thu, Jan 25, 2018, 11:19 Gabor Grothendieck
2023 Nov 14
1
data.frame weirdness
On Tue, 14 Nov 2023 at 09:41, Gabor Grothendieck
<ggrothendieck at gmail.com> wrote:
>
> Also why should that difference result in different behavior?
That's justifiable, I think; consider:
> d1 = data.frame(a = 1:4)
> d2 = d3 = data.frame(b = 1:2)
> row.names(d3) = c("a", "b")
> data.frame(d1, d2)
a b
1 1 1
2 2 2
3 3 1
4 4 2
> data.frame(d1,