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How to initialise a string from NSData in Swift
...tastring = NSString(data: fooData, encoding: NSUTF8StringEncoding)
Swift 3 or newer:
let datastring = NSString(data: fooData, encoding: String.Encoding.utf8.rawValue)
This doc explains the syntax.
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What regular expression will match valid international phone numbers?
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Sorting multiple keys with Unix sort
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Ken GentleKen Gentle
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7
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Concatenate a vector of strings/character
...ta, collapse = '')
Thanks to http://twitter.com/onelinetips/status/7491806343
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Get the first item from an iterable that matches a condition
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How to sort objects by multiple keys in Python?
... case you like your code terse.
Later 2016-01-17
This works with python3 (which eliminated the cmp argument to sort):
from operator import itemgetter as i
from functools import cmp_to_key
def cmp(x, y):
"""
Replacement for built-in function cmp that was removed in Python 3
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Why is rbindlist “better” than rbind?
...d will join by position
eg
do.call(rbind, list(data.frame(a = 1:2, b = 2:3), data.frame(b = 1:2, a = 2:3)))
## a b
## 1 1 2
## 2 2 3
## 3 2 1
## 4 3 2
rbindlist(list(data.frame(a = 1:5, b = 2:6), data.frame(b = 1:5, a = 2:6)))
## a b
## 1: 1 2
## 2: 2 3
## 3: 1 2
## 4: 2 3
Some...
List comprehension vs map
...:
$ python -mtimeit -s'xs=range(10)' 'map(hex, xs)'
100000 loops, best of 3: 4.86 usec per loop
$ python -mtimeit -s'xs=range(10)' '[hex(x) for x in xs]'
100000 loops, best of 3: 5.58 usec per loop
An example of how performance comparison gets completely reversed when map needs a lambda:
$ pytho...
Checking if array is multidimensional or not?
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The short answer is no you can't do it without at least looping implicitly if the 'second dimen...
Difference between float and decimal data type
...mysql> insert into numbers values (100, 100);
mysql> select @a := (a/3), @b := (b/3), @a * 3, @b * 3 from numbers \G
*************************** 1. row ***************************
@a := (a/3): 33.333333333
@b := (b/3): 33.333333333333
@a + @a + @a: 99.999999999000000000000000000000
@b + @b...