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How do you send a HEAD HTTP request in Python 2?
...he requests library as mentioned by other answers below.
Use httplib.
>>> import httplib
>>> conn = httplib.HTTPConnection("www.google.com")
>>> conn.request("HEAD", "/index.html")
>>> res = conn.getresponse()
>>> print res.status, res.reason
200 OK
&...
Eloquent Collection: Counting and Detect Empty
...whether an Eloquent collection returned from $result = Model::where(...)->get() is empty, as well as counting the number of elements.
...
Why does the order of the loops affect performance when iterating over a 2D array?
...
Nothing to do with assembly. This is due to cache misses.
C multidimensional arrays are stored with the last dimension as the fastest. So the first version will miss the cache on every iteration, whereas the second version won't. So the second version should be substantially faster.
...
Comparing two dictionaries and checking how many (key, value) pairs are equal
..., ('a',1)] (same dictionaries, different order).
For example, see this:
>>> x = dict(a=2, b=2,c=3, d=4)
>>> x
{'a': 2, 'c': 3, 'b': 2, 'd': 4}
>>> y = dict(b=2,c=3, d=4)
>>> y
{'c': 3, 'b': 2, 'd': 4}
>>> zip(x.iteritems(), y.iteritems())
[(('a', 2), ('...
How to remove a key from a Python dictionary?
...y_dict.pop(key) for removing a key from a dictionary when the key exists
>>> import timeit
>>> setup = "d = {i: i for i in range(100000)}"
>>> timeit.timeit("del d[3]", setup=setup, number=1)
1.79e-06
>>> timeit.timeit("d.pop(3)", setup=setup, number=1)
2.09e-06...
Delete an element from a dictionary
...
pop mutates the dictionary.
>>> lol = {"hello": "gdbye"}
>>> lol.pop("hello")
'gdbye'
>>> lol
{}
If you want to keep the original you could just copy it.
...
Options, Settings, Properties, Configuration, Preferences — when and why?
...n, such as "1 tab = 4 spaces". I came to this conclusion because "Tools -> Options..." gives a tree view of things that can be changed and "Tools -> Import and Export Settings..." saves to a file the choices made within "Tools -> Options...".
– Tyson Williams
...
Extracting the last n characters from a ruby string
... Rails), you can do
string.chars.last(n).join
For example:
2.4.1 :009 > a = 'abcdefghij'
=> "abcdefghij"
2.4.1 :010 > a.chars.last(5).join
=> "fghij"
2.4.1 :011 > a.chars.last(100).join
=> "abcdefghij"
If you're using Ruby on Rails, you can call methods first and last on a...
How to remove specific elements in a numpy array
...There is a numpy built-in function to help with that.
import numpy as np
>>> a = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9])
>>> b = np.array([3,4,7])
>>> c = np.setdiff1d(a,b)
>>> c
array([1, 2, 5, 6, 8, 9])
...
Insert new item in array on any position in PHP
...e", "two", "three"];
array_insert(
$arr,
1,
"one-half"
);
// ->
array (
0 => 'one',
1 => 'one-half',
2 => 'two',
3 => 'three',
)
String Usage:
$arr = [
"name" => [
"type" => "string",
"maxlength" => "30",
],
"email" =&g...