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How to get the first column of a pandas DataFrame as a Series?
... [7]: df.iloc[:,0]
Out[7]:
0 1
1 2
2 3
3 4
Name: x, dtype: int64
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In Javascript/jQuery what does (e) mean?
...(e) {
// does something
alert(e.type); //will return you click
}
DEMO - Mouse Events DEMO uses e.which and e.type
Some useful references:
http://api.jquery.com/category/events/
http://www.quirksmode.org/js/events_properties.html
http://www.javascriptkit.com/jsref/event.shtml
http://ww...
Absolute vs relative URLs
...actice to use relative URLs, so that your website will not be bound to the base URL of where it is currently deployed. For example, it will be able to work on localhost, as well as on your public domain, without modifications.
...
Using two values for one switch case statement
...pression. The following code example, ,
displays the number of the month based on the value of the String
named month:
public class StringSwitchDemo {
public static int getMonthNumber(String month) {
int monthNumber = 0;
if (month == null) {
return monthNumbe...
What is memoization and how can I use it in Python?
...emoization" → "memorandum" → to be remembered) results of method calls based on the method inputs and then returning the remembered result rather than computing the result again. You can think of it as a cache for method results. For further details, see page 387 for the definition in Introducti...
How to get the raw value an field?
...
Track all pressed keys based on their key codes
I suppose one could listen to the keyup events and keep an array of all characters entered, based on their keycodes. But it's a pretty tedious task and probably prone to bugs.
http://unixpapa.com/js...
PostgreSQL error: Fatal: role “username” does not exist
...
Use the operating system user postgres to create your database - as long as you haven't set up a database role with the necessary privileges that corresponds to your operating system user of the same name (h9uest in your case):
sudo -u postgres -i
As recommended here or here.
Th...
How to create a GUID/UUID in Python
... they keep updating)
>>> import uuid
>>> # make a UUID based on the host ID and current time
>>> uuid.uuid1()
UUID('a8098c1a-f86e-11da-bd1a-00112444be1e')
>>> # make a UUID using an MD5 hash of a namespace UUID and a name
>>> uuid.uuid3(uuid.NAMESPACE_...
Bash: infinite sleep (infinite blocking)
... was a cool thing to learn about for Linux. However, while true; do sleep 86400; done ought to be an adequate substitute.
– Ivan X
Feb 1 '15 at 10:26
...
What's the correct way to convert bytes to a hex string in Python 3?
... convenient transformations like quoted-printable (fits into 7bits ascii), base64 (fits into alphanumerics), hex escaping, gzip and bz2 compression. In Python 2, you could do:
b'foo'.encode('hex')
In Python 3, str.encode / bytes.decode are strictly for bytes<->str conversions. Instead, you...