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dplyr: “Error in n(): function should not be called directly”
...ction" specification, like example below:
delay <- dplyr::summarise(by_tailnum,
count = n(),
dist = mean(distance, na.rm = TRUE),
delay = mean(arr_delay, na.rm = TRUE))
share
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improv...
How to create a fixed-size array of objects
...
Fixed-length arrays are not yet supported. What does that actually mean? Not that you can't create an array of n many things — obviously you can just do let a = [ 1, 2, 3 ] to get an array of three Ints. It means simply that array size is not something that you can declare as type inf...
What is the difference between is_a and instanceof?
...ut PHP versions >= 5.3.9 now accept an optional third boolean argument $allow_string (defaults to false) to allow comparisons of string class names instead:
class MyBaseClass {}
class MyExtendingClass extends MyBaseClass {}
// Original behavior, evaluates to false.
is_a(MyExtendingClass::class,...
Retrieve list of tasks in a queue in Celery
... the queue.
You should look here:
Celery Guide - Inspecting Workers
Basically this:
from celery.app.control import Inspect
# Inspect all nodes.
i = Inspect()
# Show the items that have an ETA or are scheduled for later processing
i.scheduled()
# Show tasks that are currently active.
i.active()...
Running Python code in Vim
...th python
Explanation:
autocmd: command that Vim will execute automatically on {event} (here: if you open a python file)
[i]map: creates a keyboard shortcut to <F9> in insert/normal mode
<buffer>: If multiple buffers/files are open: just use the active one
<esc>: leaving insert...
How to create SBT project with IntelliJ Idea?
...Sbt developing, and I'd like to import a Sbt project in IntelliJ Idea.
Actually, I managed to import my project in two different ways:
...
Adding Only Untracked Files
...where I've interactively added some updates to the index and I want to add all of the untracked files to that index before I commit.
...
How can I create a link to a local file on a locally-run web page?
...a>
These will never open the file in your local applications automatically. That's for security reasons which I'll cover in the last section. If it opens, it will only ever open in the browser. If your browser can display the file, it will, otherwise it will probably ask you if you want to down...
How do I grant myself admin access to a local SQL Server instance?
I installed SQL Server 2008 R2 to my local machine. But, I can't create a new database because of rights (or lack of).
6 An...
How can I get Express to output nicely formatted HTML?
...
This worked, but I had to install a bunch of extra dependencies, namely promise, uglify-js, css and lexical-scope before it would run again (it would build, but crash on first request). I only added that one line.
– CWSpear
...