similar to: zoo object

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

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

Gabor, Thanks much. Your solution is elegant. My overall scheme is to take present date, and check whether it is a weekend, if not, then create a string based on the date, to concatenate into a url link for download.file( ). The files I need to download have a part which is in the format: mmddyy. I am working to make myself a system to connect to exchanges, and download end of day files from

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

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

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

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

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

Sir , I want to implement email section in ma web application.. so i found the method ''server_setting'' for it... Following is the method: config.action_mailer.server_settings = { :address => "smtp.gmail.com" , :port => 25, :domain => "gmail.com" , :authentication => :login, :user_name => "manish" , :password =>

*** BLURB HERE *** Bean Huo (5): fs/buffer: clean up block_commit_write fs/buffer.c: convert block_commit_write to return void ext4: No need to check return value of block_commit_write() fs/ocfs2: No need to check return value of block_commit_write() udf: No need to check return value of block_commit_write() fs/buffer.c | 24 +++++++-----------------

Hello, In a way similar to speexclient voip example, I want to have a voip application where 3 or more users can interact. This creates the following problems "1. How to playback 2 or more audio streams such that they appear overlayed (parallel)". The audio streams are speex encoded. I have few approaches in mind. 1. Create multiple decoder states and multiple ALSA audio playback

Hi Matt, All, Thanks for looking into this and your suggestions. I compiled the program with -O3 optimization level (clang -O3) on X86_64 target. After your suggestion, i ran the program with iteration of 10000 runs and found that average runtimes are (attaching data collected as well) Forward loop traverse : 2.006 milli seconds Reverse loop traverse : 1.531 milli seconds Yes, i agree that

Hi Vishal, Ruijie, Thanks for your interest in the project. To get started, the first task would be to merge the 5 patches on top of trunk llvm. The list of patches are listed in the project description: http://llvm.org/OpenProjects.html#llvm_mergesim Please create an account in llvm phabricator (reviews.llvm.org) if you haven't already, and put your patches there. Let me know if you have

Hi useR's, Has anyone used the "Lars" package in R before? If so, is there any tutorial (not manual) or worked out example online for this R package that one can go through to figure out how one can use this package with lasso regression? I appreciate any help I can get in this direction. Sincerely, Vishal -- *Vishal Thapar, Ph.D.* *Scientific informatics Analyst Cold Spring

Hi All, Did anyone else have a problem like this? I am sorry if its a small issue, I seem to not understand what to do to get rid of this error. > Sigma [1] 0.1939025 > MuRest [1] 8.512772 > TauZero [1] 0.1 > curve(qlnorm(x,-TauZero+MuRest, Sigma,lower.tail=F), xlim=c(4000,9000), ylim=c(0,.99),xlab="", ylab="") Warning message: In qlnorm(p, meanlog, sdlog,

Hi, I am very very new to both Ruby and Ruby on Rails. I have been given a task to create a web application, which is able to edit individual entries in a key-value file. In other works, I would need to create an application which can parse a key-value file. Could someone guide me where I should start in a case like that? I was able to access and edit database table entries using Rails, but I

I am using Rails 1.2.3 and Active scaffold 1.1.1 My requirement is to send the export of users data weekly to the admin as email via cron. How can i automate the process of exporting csv and storing it at a place? So that i can pick it from there and attach to the email before sending? -- Posted via http://www.ruby-forum.com/. -- You received this message because you are subscribed to the

Hi useR's, I am resending this request since I got no response for my last post and I am new to the list so pardon me if I am violating the protocol. I am trying to use the "Kernlab" package for training and prediction using SVM's. I am getting the following error when I am trying to use the predict function: > predictSvm = predict(modelforSVM, testSeq); Error in

Hi. Can anyone point me to any module in R which implements "Little's Chi Square test" for MCAR. The problem is that i have around 60 behavioural variables on a 6 point categorical scale which i need to test for MCAR and MAR. What i can make out from preliminary analysis is that moderate (0.30 to 0.60) correlations may be present in several variable pairs leading me to suspect

Hi, I have been studying LLVM infrastructure from past 1 month and trying out some hands on to get familiar with it. I am keen to propose loop reversal pass in LLVM as a part of GSoC 2015. Following are the details of my proposal. A for loop can run in two ways – it can count up or it can count down. 1. for(i=0; i<10 ;i++) {// Do something} 2. for(i=9; i--;) {// Do something}