Category "data.table"

How to get week numbers from dates?

Looking for a function in R to convert dates into week numbers (of year) I went for week from package data.table. However, I observed some strange behaviour: &

Perform row-wise operation in datatable with multiple elements

I have the following data table: library(data.table) set.seed(1) DT <- data.table(ind=1:100,x=sample(100),y=sample(100),group=c(rep("A",50),rep("B",50))) No

Simultaneously remove the first and last rows of a data frame until reaching a row that does not have an NA

I have a dataframe that contains NA values, and I want to remove some rows that have an NA (i.e., not complete cases). However, I only want to remove rows at th

Flagging continuous observations and creating enrolment spans

I have a few large enrolment datasets and I'm trying to create two things: I'd like to flag each uninterrupted monthly observation (final_df1) I'd like to creat

How to do sum and filter in rbind function

I am using an R package which extracts data from tables in a database based on the flag for each table. If the flag is 1, extract data from that table. If the f

Extracting rows based on more than two partial strings that must all be part of the string

I want to extract rows that must contain two or more partial strings. For example, suppose I have the following data.table df <- data.table(player = c('A', '

Filling a column based on the value of another column in data.table

I have data as follows: dat <- structure(list(amount_of_categories = c(2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 1L, 1L, 1L ), mun

use 'start' and 'end' values in two columns to specify fill range over remaining columns in R

I need to fill each row of a matrix with '1' between 'start' and 'end' columns, where the 'start' and 'end' column names (dates in the real data) are specified

use 'start' and 'end' values in two columns to specify fill range over remaining columns in R

I need to fill each row of a matrix with '1' between 'start' and 'end' columns, where the 'start' and 'end' column names (dates in the real data) are specified

Using R to Calculate the time since binary output=1

I have binary data in a dataframe with a time feature and I'm looking to produce a dataframe like below with a new column "duration since =1". I was able to fi

dplyr: Replace multiple values based on condition in a selection of columns

I try to conditionally replace multiple values in a data frame. In the following data set, I want to replace in columns 3:5 all values of 2 by "X" and all value

Using setDT inside a function

I'm writing a function that, among other things, coerces the input into a data.table. library(data.table) df <- data.frame(id = 1:10) f <- function(df){

data.table foverlaps with as.yearmon wrong result

I am trying to use foverlaps from the data.table package. When I use it together with as.yearmon I get wrong results. Here is a small example: library(data.tabl

R data.table struggling with conditional subsetting when column name is predefined elsewhere

Let's say I have a data table library(data.table) DT <- data.table(x=c(1,1,0,0),y=c(0,1,2,3)) column_name <- "x" x y 1: 1 0 2: 1 1 3: 0 2 4: 0 3 And

Making a while loop more efficient for use on a large data.table to delete rows based on certain conditions

I have a pretty big amount of data in a data table. I would like to delete a number of rows if there is a certain value in a cell. Below is an excerpt from my d

R - Data.table - Using variable column names in RHS operations

How do I use variable column names on the RHS of := operations? For example, given this data.table "dt", I'd like to create two new columns, "first_y" and "firs

Combination of all pairs of rows using R

Here is my dataset: data <- read.table(header = TRUE, text = " group index group_index x y z a 1 a1 12 13 14 a 2 a2

data.table join with date

hello im trying to extract some id with a group and Date in range > d1 id group Date 1: 1 A 2017-07-02 2: 2 A 2017-07-04 3: 3 A

fread does not read character vector

I am trying to download a list using R with the following code: name <- paste0("https://www.sec.gov/Archives/edgar/full-index/2016/QTR1/master.idx") master

How to map values from a data.table to a data.table (R)

I have two map/data.tables. One consists of key-values and another one just of some keys. I want to map the values from the first map to the keys of the second.

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