Displaying 20 results from an estimated 8157 matches for "mathematics".
2012 May 15
2
question about creating data frame
Hello,
My data is "study.txt":
"Not A" "A"
"Mathematics" 80 15
"Physics" 32 24
"Biology" 18 29
I want to transform this data into with column names 'course' and 'A':
course A
1 Mathematics 1
2 Mathematics 1...
2006 Jun 06
5
ruby mathematical expression parser
Hi,
Has anyone come across a Ruby mathematical expression parser, capable
of parsing out token, replacing them with values then executing the
mathematical formula? Nothing too heavy, A * (44/12) * ... etc. where
A is can be replaced with a value.
In Java there are serveral, like JEP, but I''d prefer it we could get a
Ruby one now we have moved over to Rails, otherwise we will have to
2007 Nov 19
2
Editorial in Notices of the AMS: Open Source Mathematical Software
Hi all,
For those interested, while scanning /. tonight, I came across a posting
which referred to a new editorial in the November 2007 Notices of the
American Mathematical Society:
Open Source Mathematical Software
by David Joyner and William Stein
http://www.ams.org/notices/200710/tx071001279p.pdf
Although brief, it makes for interesting reading.
Regards,
Marc Schwartz
1997 Sep 11
1
R-alpha: Mathematical Annotation in R (plots)
[[ this has first bounced to me as 'list-manager', because the
subject said ``Returned mail: User unknown''
Paul, I assume you'd approve the subject I've chosen...
-- Martin M
]]
hi
for those who are interested ...
the following is a LaTeX document which describes the current state of
mathematical expression syntax in R
paul
------CUT
2009 Jun 17
0
New book: Mathematical modeling using R
...uately used, help to reduce
experimental costs by a better exploration of the information content
of experimental data...
Marcello Vasta, Meccanica, International Journal of Theoretical and
Applied Mechanics
?? With its focus on applications, this book is for readers with just
a basic knowledge of
mathematics. The chapters develop any advanced theory that is required...?
Idalia Flores, Computing Reviews, Association for Computing Machinery, New York
?... The author takes up quite a large number of topics ? he is
clearly an enthusiastic teacher ? (he) has broad experience and
expertise to share with stu...
2011 Jun 20
1
Can mathematical formula be used in the help file of a R function or package?
Hi everyone,
I am writing help files for some R functions in an R package. I am wondering
if we can use the Latex mathematical formula when editing those *.Rd files
and then obtain a pdf manual with beautiful mathematical formula. I tried it
with the default R CMD check command but could not get the desired
mathematical formula. That is, $f(x)$ is not recognized as a math formulas.
I think the
2011 Sep 13
2
Mathematical expressions in the group labels in lattice
Hi,
I am working with the lattice package and I want to label to groups in the xyplots with mathematical expressions.
I short example for this
library(lattice)
Case<-factor(rep(1:2,each=300))
xx<-rnorm(600,0,1)
yy<-rnorm(600,0,1)
xyplot(yy~xx|Case)
This results in two scatter plots with label "1" and "2". I would like to substitute this labels by math expression. I
2005 Apr 04
3
plotting mathematical notation and values substitution
Dear R-users,
I'm trying to add a title on a plot with both mathematical notation and
values substitution. I read the documentation and search the mailing list
but I was not able to solve my problem. Actually, there is a message by
Uwe Ligges on June 2003 which addresses a question very close to mine, but
the code provided doesn't work. The code is the following:
# I add this to let you
2002 Mar 12
1
mathematical expression in legend
Hello,
I'm trying to put a mathematical expression into a legend, but R
complains about a syntax error. Basically i'd like to do this:
legend.text = c(expression(x < 10), expression(x >= 10))
The manual says that one can only pass mathematical expressions to axis,
text etc. but not to the legend command?
Is there a workaround for this?
thanks a lot for help,
Arne
--
Arne
2009 Mar 31
1
Problem with mathematical expression and loop
Hi to all
I use a loop to plot 9 different histograms of 9 different
transformations of one dataset (x).
I want to label the histograms with the mathematical expression of each
transformation (e.g. x^3). For that I've prepared a vector with the
labeling names for "expression".
> trans.expr <- c("x^3", "x^2", "x", "frac(1,x)",
2010 Jun 28
1
mathematical expression in varnames of lattice parallel plot
How can I insert mathematical expressions for variable names in a
lattice parallel plot? I tried to implement mathematical expressions in
varnames, however, without success.
For example, neither
parallel(~iris[1:4] | Species, iris,
varnames=c("P[Width]", "Petal[length]", "alpha[Width]", "Sepal[Length]"))
nor
parallel(~iris[1:4] | Species,
2003 Apr 03
0
Call for papers
...f Institute for Mathematical Research -
Universiti Putera Malaysia, Malaysia)
- Contributed Papers
- Meeting on the establishment of Muslim Association of
Statistical and Mathematical Sciences in South East Asia.
April 26, 2003
- Invited Papers
Prof. Dr. Ismail Mohammad
(Head of Department of Mathematics - Kolej Universiti
Sains dan Teknologi Malaysia, Malaysia)
Dr. Aunuddin
(Director of Research Institute - Insitut Pertanian Bogor,
Indonesia)
Suwanda, MSc.
(Department of Statistics - Universitas Islam Bandung,
Indonesia)
- Contributed Papers
- Studium Generale
- Closing Ceremony
Participatio...
2007 Jan 03
1
mathematical symbols in plots
Hello everyone!
I'm trying to plot some mathematical expression along my axis, but
demo(plotmath) did not have the symbol I was looking for. In particular,
I would like to denote the mean of an observable by writing
<k>
which I tried to enter with
expression(group("<", k, ">"))
However, my naive try doesn't work and the help doesn't want to tell me,
2010 Apr 26
1
Error in pf(q, df1, df2, lower.tail, log.p) : Non-numeric argument to mathematical function
inputfille
snpid indid genotype gvariable probeid gene geneexpression
rs1040480 CHB_NA18524 C/T 2 GI_19743926-I PTPRT 5.850586
rs1040480 CHB_NA18526 C/C 1 GI_19743926-I PTPRT 6.028641
rs1040480 CHB_NA18529 C/C 3 GI_19743926-I PTPRT 5.944392
rs1040481 CHB_NA18532 C/C 1 GI_19743926-I PTPRT 5.938578
rs1040481 CHB_NA18537 C/C 2 GI_19743926-I PTPRT 5.874439
rs1040481 CHB_NA18540 C/C 3 GI_19743926-I
2011 Mar 07
0
JOB: Statistical and Mathematical Modelling in the Energy and Environment Sectors
JOB: Statistical and Mathematical Modelling in the Energy and Environment
Sectors
Quintessa (www.quintessa.org) is an employee-owned company that undertakes
high-quality science-based consultancy, research and software development
for industry and governments around the world in the energy and environment
sectors. Statistical and mathematical modelling of complex systems (ranging
from geological
2008 May 08
1
variable of mathematics string not interpreted
Hi everybody,
my goal is to display symbols on the x-axis of a barplot.
I read some mathematics strings in a file and convert them to an expression
as follows:
tt<- scan(file = fstr ,'what' ='character', sep = "");
for (iaa in 1:length(tt)) {
tt[iaa]<-do.call(expression, lapply(tt[iaa], as.name));
}
I obtained the following result:
tt =
expression(`alpha[...
2009 Jul 23
2
mathematical notation in R
Does this approach what you're looking for?
See
?is.finite
for more info
> LBAuo<- -9999
> LBAuo
[1] -9999
> if (LBAuo <= -9999) LBAuo <- -Inf
> LBAuo
[1] -Inf
>
HTH
Steven McKinney
> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Mary A. Marion
> Sent: Wednesday, July 22, 2009
2004 Mar 12
1
Re: [R] No traceback available when using try(...) (PR#6669)
On Fri, 12 Mar 2004 11:44:14 -0500, "Roger D. Peng" <rpeng@jhsph.edu>
wrote :
>Funny, it works for me on R-patched
>
> > f <- function(a) { return(log(a)) }
> > f("A")
>Error in log(x) : Non-numeric argument to mathematical function
> > traceback()
>2: log(a)
>1: f("A")
> > try(f("A"))
>Error in log(x) :
2012 Oct 11
4
characters, mathematical expressions and computed values
Hello,
I have to add "Age (bar(x)=14.3) as a title on a chart. I am unable to get
this to working. I have tried bquote, substitute and expression, but they
are only doing a part of the job.
new<-
c(14.3, 18.5, 18.1, 17.7, 18, 15.9, 19.6, 17.3, 17.8, 17.5, 15.4,
16.3, 15, 17.1, 17.1, 16.4, 15.2, 16.7, 16.7, 16.9, 14.5, 16.6,
15.8, 15.2, 16.2, 15.6, 15, 17.1, 16.7, 15.6, 15, 15.8, 16.8,
2012 Mar 20
3
Graphic legend with mathematical symbol, numeric variable and character variable
Hi,
I'd like to make a legend with a mix of mathematical symbol (tau),
numeric variable and character variables.I have tried :
types<-c("Type 1","Type 2","Type 2")
tau<-c(1,3,2)
legend(x="topright",legend=paste(types,"tau=",expression(tau)))
but it doesn't work: the 'tau' symbol is not written in its 'symbol