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Split column at delimiter in data frame [duplicate]
...b','b|c','x|y'))
library(splitstackshape)
cSplit(df, "FOO", "|")
# ID FOO_1 FOO_2
# 1 11 a b
# 2 12 b c
# 3 13 x y
This particular function also handles splitting multiple columns, even if each column has a different delimiter:
df <- data.frame(ID=11:13,
...
How do I read any request header in PHP
...
IF: you only need a single header, instead of all headers, the quickest method is:
<?php
// Replace XXXXXX_XXXX with the name of the header you need in UPPERCASE (and with '-' replaced by '_')
$headerStringValue = $_SERVER['HTTP_XXXXXX_XXXX'];
ELSE IF: you run PHP...
OnNotify函数 ON_NOTIFY消息总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
OnNotify函数 ON_NOTIFY消息总结函数CWnd::OnNotify处理通知消息。其默认实现是检查通知消息处理函数的消息映射,然后调用。(checks the message map for notificatio...函数CWnd::OnNotify处理通知消息。其默认实现是检查通知消息处理函数的消息...
How to make Entity Framework Data Context Readonly
...nsumer.
public class ReadOnlyDataContext
{
private readonly DbContext _dbContext;
public ReadOnlyDataContext(DbContext dbContext)
{
_dbContext = dbContext;
}
public IQueryable<TEntity> Set<TEntity>() where TEntity : class
{
return _dbContext.Set...
What exactly does += do in python?
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In Python, += is sugar coating for the __iadd__ special method, or __add__ or __radd__ if __iadd__ isn't present. The __iadd__ method of a class can do anything it wants. The list object implements it and uses it to iterate over an iterable object appending each...
How do you run a crontab in Cygwin on Windows?
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You need to also install cygrunsrv so you can set cron up as a windows service, then run cron-config.
If you want the cron jobs to send email of any output you'll also need to install either exim or ssmtp (before running cron-config.)
See /usr/...
Accessing an SQLite Database in Swift
...robably use one of the many SQLite wrappers, if you wanted to know how to call the SQLite library yourself, you would:
Configure your Swift project to handle SQLite C calls. If using Xcode 9 or later, you can simply do:
import SQLite3
Create/open database.
let fileURL = try! FileManager.default...
Suppressing “is never used” and “is never assigned to” warnings in C#
I have a HTTPSystemDefinitions.cs file in C# project which basically describes the older windows ISAPI for consumption by managed code.
...
How to print the contents of RDD?
...save in a single file, you can coalesce you RDD into one partition before calling saveAsTextFile, but again this may cause issues. I think the best option is to write in multiple files in HDFS, then use hdfs dfs --getmerge in order to merge the files
– Oussama
...
Using 'return' in a Ruby block
...; }
LocalJumpError: unexpected return
from (irb):7:in `block in irb_binding'
from (irb):2:in `call'
from (irb):2:in `thing'
from (irb):6
from /home/mirko/.rvm/rubies/ruby-1.9.1-p378/bin/irb:15:in `<main>'
irb(main):009:0> thing { break 6 * 7 }
=> 4...