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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
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Since dplyr 0.8 group_by gained the .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a)...
Matplotlib tight_layout() doesn't take into account figure suptitle
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10 Answers
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Run command on the Ansible host
...ou want to run an entire play on the Ansible host, then specify hosts: 127.0.0.1 and connection:local in the play, for example:
- name: a play that runs entirely on the ansible host
hosts: 127.0.0.1
connection: local
tasks:
- name: check out a git repository
git: repo=git://foosball.exa...
What does ** (double star/asterisk) and * (star/asterisk) do for parameters?
...s the other way around:
def foo(a, b, c):
print(a, b, c)
obj = {'b':10, 'c':'lee'}
foo(100,**obj)
# 100 10 lee
Another usage of the *l idiom is to unpack argument lists when calling a function.
def foo(bar, lee):
print(bar, lee)
l = [1,2]
foo(*l)
# 1 2
In Python 3 it is possible to...
Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?
...) and actually use true and false.
In a C compiler, this is equivalent to 0 and 1.
(note that removing the parentheses will break that due to order of operations)
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ActiveRecord: size vs count
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edited Jul 10 '12 at 22:15
Jo Liss
22.5k1414 gold badges101101 silver badges150150 bronze badges
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CSS performance relative to translateZ(0)
...ng' the GPU to think that an element is 3D by using transform: translateZ(0) to speed up animations and transitions. I was wondering if there are implications to using this transform in the following manner:
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What is the Ruby (spaceship) operator?
...ther language that supports it. Basically instead of returning 1 (true) or 0 (false) depending on whether the arguments are equal or unequal, the spaceship operator will return 1, 0, or −1 depending on the value of the left argument relative to the right argument.
a <=> b :=
if a < b t...
How to generate keyboard events in Python?
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+50
It can be done using ctypes:
import ctypes
from ctypes import wintypes
import time
user32 = ctypes.WinDLL('user32', use_last_error=T...
How are multi-dimensional arrays formatted in memory?
...things are going to happen. Here's a quick example:
int array1[3][2] = {{0, 1}, {2, 3}, {4, 5}};
In memory looks like this:
0 1 2 3 4 5
exactly the same as:
int array2[6] = { 0, 1, 2, 3, 4, 5 };
But if you try to pass array1 to this function:
void function1(int **a);
you'll get a warnin...