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Assign multiple columns using := in data.table, by group
...
This now works in v1.8.3 on R-Forge. Thanks for highlighting it!
x <- data.table(a = 1:3, b = 1:6)
f <- function(x) {list("hi", "hello")}
x[ , c("col1", "col2") := f(), by = a][]
# a b col1 col2
# 1: 1 1 hi hello
# ...
How to simulate the environment cron executes a script with?
...e, turn it back off, then run
env - `cat ~/cronenv` /bin/sh
And you are now inside a sh session which has cron's environment
Bring your environment to cron
You could skip above exercise and just do a . ~/.profile in front of your cron job, e.g.
* * * * * . ~/.profile; your_command
Use screen
...
ASP.NET MVC 5 - Identity. How to get current ApplicationUser
...he past 2 years) but the API is consistent. For example the users table is now called AspNetUsers in Identity Framework, and the names of several primary key fields kept changing, so the code in several answers will no longer work as-is.
Another problem is that the underlying OWIN access to the dat...
Django: How to completely uninstall a Django app?
...py makemigrations -n drop_all_tables my_app_to_remove
The directory looks now like this:
my_app_to_remove/
my_app_to_remove/__init__.py
my_app_to_remove/migrations
my_app_to_remove/migrations/0001_initial.py
my_app_to_remove/migrations/....
my_app_to_remove/migrations/0030_drop_all_tables.py
my_ap...
What is Node.js? [closed]
...vent loops with first class function objects and closures. People already know how to use it this way having used it in the browser to respond to user initiated events.
A lot of people already know JavaScript, even people who do not claim to be programmers. It is arguably the most popular programmin...
How to increase storage for Android Emulator? (INSTALL_FAILED_INSUFFICIENT_STORAGE)
...o it manually by opening the AVD's pull-down menu and choosing Wipe Data.
Now start and use your Emulator with increased storage.
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What methods of ‘clearfix’ can I use?
...z' of CSS Mojo has pointed out that when targeting modern browsers, we can now drop the zoom and ::before property/values and simply use:
.container::after {
content: "";
display: table;
clear: both;
}
This solution does not support for IE 6/7 …on purpose!
Thierry also offers: "A w...
How to add to an existing hash in Ruby
...'
# This is then available immediately
hash[:b]
# => "Bee"
# The hash now contains both keys
hash
# => { :a => 'a', :b => 'Bee' }
Ruby on Rails confuses this somewhat by providing HashWithIndifferentAccess where it will convert freely between Symbol and String methods of addressing.
...
How do I uninstall nodejs installed from pkg (Mac OS X)?
I installed NodeJS from pkg file on my Mac. Now I need to uninstall it. Tell me please how to do it.
I tried to remove files from this list:
...
How do I add more members to my ENUM-type column in MySQL?
... of countries which would make for a rather large and awkward enum.
EDIT: Now that I can see your error message:
ERROR 1265 (01000): Data truncated for column 'country' at row 1.
I suspect you have some values in your country column that do not appear in your ENUM. What is the output of the follo...