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Get push notification while App in foreground iOS
... app received push notifications in foreground
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void)
{
completionHandler([.alert, .badge, .sound...
How to implement a queue using two stacks?
...ions, so it's a perfectly linear O(n) algorithm.
– LP_
Jan 17 '14 at 11:56
1
@LP_ it takes quadra...
Explain how finding cycle start node in cycle linked list work?
... @Passionate: Take mu steps from the start point to get to X_mu, the start of the cycle (by definition of mu). Then if you take i more steps, where i is a multiple of the cycle length, you end up back at the cycle start: X_mu + i = X_mu. But addition is commutative, so this is equiva...
What is the correct way of using C++11's range-based for?
...t class, with custom copy semantics.
class X
{
public:
X()
: m_data(0)
{}
X(int data)
: m_data(data)
{}
~X()
{}
X(const X& other)
: m_data(other.m_data)
{ cout << "X copy ctor.\n"; }
X& operator=(const X& other)
...
How to reference a file for variables using Bash?
...source
For example:
config.sh
#!/usr/bin/env bash
production="liveschool_joe"
playschool="playschool_joe"
echo $playschool
script.sh
#!/usr/bin/env bash
source config.sh
echo $production
Note that the output from sh ./script.sh in this example is:
~$ sh ./script.sh
playschool_joe
livescho...
Phonegap Cordova installation Windows
...Data\Roaming\npm\cordova -> C:\Users\binaryuser\AppData\Roaming\npm\node_modules\cordova\bin\cordova
cordova@3.0.9 C:\Users\binaryuser\AppData\Roaming\npm\node_modules\cordova
├── ncallbacks@1.0.0
├── open@0.0.3
├── colors@0.6.2
├── semver@1.1.0
├── shelljs@0.1.2
├...
Moving average or running mean
...ode below works great.
mylist = [1, 2, 3, 4, 5, 6, 7]
N = 3
cumsum, moving_aves = [0], []
for i, x in enumerate(mylist, 1):
cumsum.append(cumsum[i-1] + x)
if i>=N:
moving_ave = (cumsum[i] - cumsum[i-N])/N
#can do stuff with moving_ave here
moving_aves.append(movi...
Computed / calculated / virtual / derived columns in PostgreSQL
...al, but makes makes life a bit easier).
Suppose my computation is md5(some_string_field), then I create the index as:
CREATE INDEX some_string_field_md5_index ON some_table(MD5(some_string_field));
Now, any queries that act on MD5(some_string_field) will use the index rather than computing it f...
Escape regex special characters in a Python string
...ule instead of re. An example would be regex.escape(pattern,string,special_only=True
– Lokinou
Nov 5 '18 at 9:29
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How can I start PostgreSQL server on Mac OS X?
...omatically. For more information, run brew info postgres.
Start manually
pg_ctl -D /usr/local/var/postgres start
Stop manually
pg_ctl -D /usr/local/var/postgres stop
Start automatically
"To have launchd start postgresql now and restart at login:"
brew services start postgresql
What is the result of...