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Add a new element to an array without specifying the index in Bash
... all remaining elems. starting at the following elem.: - If start >= 0: from the elem. whose index is >= start. - If start < 0: from the elem. whose index is (last array index + 1) - abs(start); CAVEAT: if abs(start) > (last array index + 1), a null string is returned. If count is specif...
Using braces with dynamic variable names in PHP
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from phpNET manual php.net/manual/ru/language.variables.variable.php $price_for_monday = 10; $price_for_tuesday = 20; $today = 'tuesday'; $price_for_today = ${ 'price_for_' . $today}; echo $price_for_today; // will return 2...
\d is less efficient than [0-9]
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From Regular Expression Options: "Enable ECMAScript-compliant behavior for the expression."
– chrisaycock
May 20 '13 at 1:58
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Post-increment and pre-increment within a 'for' loop produce same output [duplicate]
...i);
++i;
}
Note that the lines i++; and ++i; have the same semantics FROM THE PERSPECTIVE OF THIS BLOCK OF CODE. They both have the same effect on the value of i (increment it by one) and therefore have the same effect on the behavior of these loops.
Note that there would be a difference if t...
Difference between == and ===
...er two object references both refer to the same object instance.
Excerpt From: Apple Inc. “The Swift Programming Language.” iBooks. https://itun.es/us/jEUH0.l
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What is the easiest way to initialize a std::vector with hardcoded elements?
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If "list-initialization of an aggregate from an object of the same type" is your thing, probably there are bigger problems in your codebase... I can think of no application where it would justify the debugging problems.
– Adam Erickson
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Understanding colors on Android (six characters)
...green and blue respectively).
So by removing the final 55 you're changing from A=B4, R=55, G=55, B=55 (a mostly transparent grey), to R=B4, G=55, B=55 (a fully-non-transparent dusky pinky).
See the "Color" documentation for the supported formats.
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What causes java.lang.IncompatibleClassChangeError?
...any java.lang.IncompatibleClassChangeError s when I try to invoke methods from it. These errors seem to appear at random. What kinds of problems could be causing this error?
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how do you filter pandas dataframes by multiple columns
... (df[Year]==2014)]
To store your dataframes in a dict using a for loop:
from collections import defaultdict
dic={}
for g in ['male', 'female']:
dic[g]=defaultdict(dict)
for y in [2013, 2014]:
dic[g][y]=df[(df[Gender]==g) & (df[Year]==y)] #store the DataFrames to a dict of dict
EDIT:...
Wait for a process to finish
...acOS, for example, implements BSD's kqueue), but not all make it available from command-line.
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