Displaying 20 results from an estimated 1000 matches similar to: "String concatenation, File Path Handling to pass to download.file( ) [backslash in DOS paths]"
2007 Oct 16
1
try / tryCatch for download.file( ) within a for loop when URL does not exist
I am trying to download a bunch of files from a server, for which I am
using download.file( ) within a for loop. The script is working fine
except until download.file hits a URL which has no file, at which
point it exits. I want to change this behavior to simple log the
failure and maintain state within the for loop and iterate to next. I
read about try / tryCatch but am having trouble
2007 Oct 15
3
for loop if else conditional
date <- as.POSIXlt(Sys.time()) #present date
for (i in 1:difftime(as.POSIXlt(Sys.Date()),"2007-10-01"))
if (date$wday != 0 & date$wday != 6) {print(date);assign("date",
(date-86400))} else (assign("date", (date-86400)))
I am trying to print dates from present day to a day in the past, but
omitting weekends. I am not doing something right, but can't
2008 Jan 10
5
diff in a dataframe
I have a dataframe say:
date price_g price_s
0.34 0.56
0.36 0.76
. .
. .
. .
and so on. say, 1000 rows.
Is it possible to add two columns to this dataframe, by computing say
diff(log(price_g) and diff(log(price_s)) ?
The elements in the first row of these columns cannot be computed, but
2008 Apr 04
1
RODBC / odbcConnectExcel Issue
Can someone throw light on the following problem I am having with RODBC?
There's an Excel file I am trying to read from, it has one sheet named
'nameclass'.
Thanks in anticipation.
Vishal Belsare
> library(RODBC)
> con = odbcConnectExcel(file.choose())
> tbls <- sqlTables(con)
> tbls
TABLE_CAT TABLE_SCHEM TABLE_NAME TABLE_TYPE REMARKS
1
2009 Mar 26
1
ApEn (Approximate Entropy), Total Corr, Information Interaction
Is there any existing implementation in R/S of :
1] Pincus & Kalman's approximate entropy (ApEn) measure
2] Total Correlation / Multiinformation
3] Information Interaction
A search doesn't quite reveal anything, but I'd be keen to not
reinvent in case someone has worked on it. Many thanks in
anticipation.
Best,
Vishal Belsare
2008 Jan 14
1
zoo object
I have an ordered series of 3 month t-bill rates (annual). I transform
this to a daily series, however, the observations are constructed only
from the dates on which the t-bills were issued, which is every week.
So now I have ordered observations of the daily 'risk-free rate' for
one day every week. I want to expand this zoo object to give a value
for every day, and to do so, copy the
2008 May 25
1
n Realizations of a Stochastic Process assigned to dynamically generated variable names?
I am interested in creating multiple (say 1000) time series, from a
given stochastic process, of length 250. I want to refer to each
realization with its own variable name, of the format say, tsn, where
n is the n'th simulation. i.e. ts1, ts2, ts3, ts4, .... , ts1000
The way I am thinking of doing this is placing the following code
within another loop, and the 'tsn' assignment should
2008 May 31
1
Representing 'Date' as 'Year - Quarter'
I have financial data on a a set of firms, with a quarterly period
(fundamental data). The data spans 10 years, and four quarters per
year. The present file (.csv) reads the Date columns as "200706" for
the second quarter of 2007; "199809" for the third quarter of 1997.
Is there a way I can convert it to something like "2007 Q2", "1998 Q3"?
I am aware of
2005 Apr 22
2
help with POSIX
For the r script below
>datestr <- "01/01/2004"
>as.POSIXct(as.Date(datestr, "%d/%m/%Y"))
I get the following output
"2003-12-31 18:00:00 Central Standard Time"
Why is the date a day before. I guess its something to do with the time, but is there a way to get it to return 2004-01-01 instead?
Thanks in advance...
-Sandeep
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2006 Dec 28
3
Dates in R
Hello all,
Can somebody point me to references or provide some code on dealing with
this date issue. Basically, I have two vectors of values that represent
dates. I want to convert these values into a date format and subtract the
differences to show elapsed time in days. More specifically, here is the
example:
Date1 Date2
032398 061585
032398 061585
111694 101994
111694
2008 Dec 11
3
getting ISO week
Hi all,
Is there a simple function already implemented for getting the ISO
weeks of a Date object?
I couldn't find one, and so wrote my own function to do it, but would
appreciate a pointer to the "default" way. If a function is not yet
implemented, could the code below be of interest to submit to CRAN?
Best Regards,
Gustaf
--------------------
2024 May 09
2
Strange variable names in factor regression
On converting character variables to ordered factors, regression result
has strange names. Is it possible to obtain same variable names with
and without intercept?
Thanks,
Naresh
mydf <- data.frame(date = seq.Date(as.Date("2024-01-01"),
as.Date("2024-03-31"), by = 1))
mydf[, "wday"] <- weekdays(mydf$date, abbreviate = TRUE)
mydf.work <- subset(mydf, !(wday
2001 Jan 03
1
package/ date/ download problem
Colleagues
I want to download the package "date" from CRAN <http://cran.r-
project.org/> to get the R-scripts (for version 1.2.0)
*** date/INDEX ***
as.date Coerce Data to Dates
date.ddmmmyy Format a Julian date
date.mdy Convert from Julian Dates to Month, Day, and Year
date.mmddyy Format a Julian date
date.mmddyyyy Format a Julian date
date.object Date Objects
mdy.date
2011 Jul 17
3
How to convert number (matlab) to date
Hello
I am new to R and I need to convert some dates (numeric format by matlab) to actual dates in R.
For instance,
Matlab -> 730456 -> >> datestr(730456)
ans =
02-Dec-1999
R -
> library(zoo)
> as.Date(730456)
[1] "3969-12-03"
I don't not mind the output format but it needs to be right.
Many thanks
Ed
2013 Oct 04
2
Possible POSIXlt / wday glitch & bugs.r-project.org status
Wanted to raise two questions:
1. Is bugs.r-project.org down? I haven't been able to reach it for two or three days:
```
ping bugs.r-project.org
PING rbugs.research.att.com (207.140.168.137): 56 data bytes
Request timeout for icmp_seq 0
Request timeout for icmp_seq 1
Request timeout for icmp_seq 2
Request timeout for icmp_seq 3
Request timeout for icmp_seq 4
Request timeout for icmp_seq 5
2010 Oct 01
3
Converting a dataframe column from string to datetime
Hi,
I have a dataframe column of the form
v<-c("Fri Feb 05 20:00:01.43000 2010","Fri Feb 05 20:00:02.274000 2010","Fri Feb 05 20:00:02.274000 2010","Fri Feb 05 20:00:06.34000 2010")
I need to convert this to datetime form. I did the following..
lapply(v,function(x){strptime(x, "%a %b %d %H:%M:%OS %Y")})
This gives me a list that looks like
2003 Aug 13
1
Problems with addition in big POSIX dates
Have you noticed any problems with big dates (>=1/1/2040) in R?
Here is the bit of code that I'm having trouble with:
> test.date <- strptime("1/1/2040",format="%m/%d/%Y")
>
> unlist(test.date)
sec min hour mday mon year wday yday isdst
0 0 0 1 0 140 0 0 0
>
> date.plus.one <- as.POSIXct(test.date) +
2011 May 14
2
changing the day of the week in dates format
Dear all,
I have a question related to the POSIXlt function in R.
I have a set of dates and times, for exmaple:
startx <- as.POSIXct("2011-01-01 00:00:00")
finx <- as.POSIXct("2011-12-31 00:00:00")
daysx<- seq(startx, finx, by="24 hours")
I
want to change the dates of all the days falling on a Saturday to the
next working day (i.e. Monday). So I
2007 Jan 17
2
problem with unlist POSIX date at midnight
Dear R-users,
I use unlist of POSIX dates to extract the year, hour etc. With that I
can search for files in my database which are in the form
'yyyymmddhh_synops.txt'
However, I get stucked during midnight where unlist just gives NA's.
The script is given below, the problem accurs at acc.period[16]
(midnight). However when I write out the character, unlist works well.
But
2008 Nov 11
1
Every other week recurring event
I have the code for computing a weekly event:
(start_date..end_date).select{|d| d.wday == wday}
but I am wondering if anyone has any ideas for using this to figure
out a recurring event for every other week. Is it possible to somehow
specify every other within the .select method? Any other
implementation ideas?
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