Define df<-read.table(textConnection(\'egg 1 20 a egg 2 30 a jap 3 50 b jap 1 60 b\')) s.t. > df V1 V2 V3 V4
Define: > dats <- list( df1 = data.frame(a=sample(1:3), b = as.factor(rep(\"325.049072M\",3))),
This code works: library(plyr) x <- data.frame(V= c(\"X\", \"Y\", \"X\", \"Y\", \"Z\" ), Z = 1:5) ddply(x, .(V), function(df) sum(df$Z),.parallel=FALSE)
In the interest of replication I like to keep a codebook with meta data for each data frame. A data codebook is:
I have a general question about desktop applications. My friend and I were discussing about how application data should be managed while the application is running. We were arguing over two methods an
Good morning all. I\'m relatively new to the Visual Basic realm (although a traditional web based script developer), i\'ve come to ask you a question.I am reading data from an XML file.This local XML
I am currently working on an ASP.NET MVC2 project. This is the first time I am working on a real MVC web application. The ASP.NET MVC website really helped me to get started really fast, but I still h
I have created an app which displays information in a organized manner about cultural places. The information is subject to changes, so I want it to be downloaded from the web. But not everytime. Only
How to you typically handle roll backs for data edits in a multi-user environment? Do you identify the transaction and build a graph of any subsequent dependent transactions and then roll them all bac
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