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A Regex that will never be matched by anything
...nd only then not find the "a" and return a negative match. I see it take ~480ms to scan a ~275k line file. The converse "a^" takes about the same time, even if it might seem more efficient. On the other hand, a negative lookahead need not scan anything: "(?!x)x" (anything not followed by an x als...
Why check both isset() and !empty()
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422
This is completely redundant. empty is more or less shorthand for !isset($foo) || !$foo, and !...
How to construct a timedelta object from a simple string
...as a string. The user must enter something like "32m" or "2h32m", or even "4:13" or "5hr34m56s"... Is there a library or something that has this sort of thing already implemented?
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What are bitwise operators?
... For example, reading an integer from four bytes:
int val = (A << 24) | (B << 16) | (C << 8) | D;
Assuming that A is the most-significant byte and D the least. It would end up as:
A = 01000000
B = 00000101
C = 00101011
D = 11100011
val = 01000000 00000101 00101011 11100011
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How do I create a namespace package in Python?
...ce packages.
Python 3.3 introduces implicit namespace packages, see PEP 420.
This means there are now three types of object that can be created by an import foo:
A module represented by a foo.py file
A regular package, represented by a directory foo containing an __init__.py file
A namespace p...
Rebasing and what does one mean by rebasing pushed commits
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4 Answers
4
Active
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How to nicely format floating numbers to String without unnecessary decimal 0?
An 64-bit double can represent integer +/- 2 53 exactly
26 Answers
26
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How to count objects in PowerShell?
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answered Jul 17 '12 at 15:54
jumbojumbo
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Getting distance between two points based on latitude/longitude
...0
lat1 = radians(52.2296756)
lon1 = radians(21.0122287)
lat2 = radians(52.406374)
lon2 = radians(16.9251681)
dlon = lon2 - lon1
dlat = lat2 - lat1
a = sin(dlat / 2)**2 + cos(lat1) * cos(lat2) * sin(dlon / 2)**2
c = 2 * atan2(sqrt(a), sqrt(1 - a))
distance = R * c
print("Result:", distance)
prin...
UnicodeDecodeError: 'utf8' codec can't decode byte 0xa5 in position 0: invalid start byte
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Jean-Francois T.
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answered Mar 6 '14 at 6:28
Santosh GhimireSantosh Ghimire
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