How to Transpose a Data Frame in R

The easiest way to transpose a data frame is to use the transpose() function from the data.table library. For example, library(data.table) # get data data(“mtcars”) # transpose t_mtcars <- transpose(mtcars) # get row and colnames in order...

How to Add an Index column to a Data Frame in R

The easiest way to add a sequence of numbers as an index column is to use the nrow() function, for example, df$index <- 1:nrow(df) This tutorial will explain how to add a numeric ID column to a data frame with code examples. Table of contentsAdd Index Column to...

How to Iterate Over the Words of a String in C++

This tutorial will go through how to iterate over the words of a string consisting of multiple words. Table of contentsIterate Over Words using istringstreamIterate Over Words using for-loopIterate Over Words using strtokIterate Over Words using Boost LibrarySummary...

How to Iterate Through a Vector in C++

The simplest way to iterate through a vector using a for loop and the [] operator to index the vector. This tutorial will describe how to iterate through a vector with code examples. Table of contentsIterate Through a Vector Using IndexingIterate Through a Vector...