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PHP: How to use array_filter() to filter array keys?
...AY_FILTER_USE_KEY to filter by key instead of value:
$my_array = ['foo' => 1, 'hello' => 'world'];
$allowed = ['foo', 'bar'];
$filtered = array_filter(
$my_array,
function ($key) use ($allowed) {
return in_array($key, $allowed);
},
ARRAY_FILTER_USE_KEY
);
Clearly th...
How to add new item to hash
...
Create the hash:
hash = {:item1 => 1}
Add a new item to it:
hash[:item2] = 2
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...
Split a string at uppercase letters
...lit on a zero-width match in Python. But you can use re.findall instead:
>>> import re
>>> re.findall('[A-Z][^A-Z]*', 'TheLongAndWindingRoad')
['The', 'Long', 'And', 'Winding', 'Road']
>>> re.findall('[A-Z][^A-Z]*', 'ABC')
['A', 'B', 'C']
...
Subscripts in plots in R
... You can use bquote when working with subscripted variables. Say, nIter <- 2, then plot(1, 1, main = bquote(title[.(nIter)])) is exactly what you need (taken from the R-help mailing list).
– fdetsch
Jan 7 '15 at 9:55
...
Pairs from single list
...rwise(t):
it = iter(t)
return izip(it,it)
# for "pairs" of any length
def chunkwise(t, size=2):
it = iter(t)
return izip(*[it]*size)
When you want to pair all elements you obviously might need a fillvalue:
from itertools import izip_longest
def blockwise(t, size=2, fillvalue=None...
How to truncate the time on a DateTime object in Python?
...
I think this is what you're looking for...
>>> import datetime
>>> dt = datetime.datetime.now()
>>> dt = dt.replace(hour=0, minute=0, second=0, microsecond=0) # Returns a copy
>>> dt
datetime.datetime(2011, 3, 29, 0, 0)
But if you ...
Remove specific characters from a string in Python
...
>>> line = "abc#@!?efg12;:?"
>>> ''.join( c for c in line if c not in '?:!/;' )
'abc#@efg12'
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How to print a percentage value in python?
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format supports a percentage floating point precision type:
>>> print "{0:.0%}".format(1./3)
33%
If you don't want integer division, you can import Python3's division from __future__:
>>> from __future__ import division
>>> 1 / 3
0.3333333333333333
# The ...
What is the reason for having '//' in Python? [duplicate]
...one of the operands was already a floating point number.
In Python 2.X:
>>> 10/3
3
>>> # to get a floating point number from integer division:
>>> 10.0/3
3.3333333333333335
>>> float(10)/3
3.3333333333333335
In Python 3:
>>> 10/3
3.3333333333333335
&...
Laravel Eloquent groupBy() AND also return count of each group
...is working for me:
$user_info = DB::table('usermetas')
->select('browser', DB::raw('count(*) as total'))
->groupBy('browser')
->get();
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