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Python None comparison: should I use “is” or ==?
My editor warns me when I compare my_var == None , but no warning when I use my_var is None .
3 Answers
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Unable to install Maven on Windows: “JAVA_HOME is set to an invalid directory”
...e-maven-2.2.0\bin" is on your command search path.
Make sure that the JAVA_HOME variable refers to the home directory for your Java installation. If you are executing Java from "E:\Sun\SDK\jdk\bin", then the JAVA_HOME variable needs to point to "E:\Sun\SDK\jdk".
NB: JAVA_HOME should NOT end with "...
What is the definition of “interface” in object oriented programming
...dom.randint(0,10)
# What you care about
class SecretGame(object):
def __init__(self, number_generator):
number = number_generator.generate()
print number
Here, none of the classes implement an interface. Python does not care about that, because the SecretGame class will just t...
Sort hash by key, return hash in Ruby
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In Ruby 2.1 it is simple:
h.sort.to_h
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Android Gallery on Android 4.4 (KitKat) returns different URI for Intent.ACTION_GET_CONTENT
Before KitKat (or before the new Gallery) the Intent.ACTION_GET_CONTENT returned a URI like this
19 Answers
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Convert Python dictionary to JSON array
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If you are fine with non-printable symbols in your json, then add ensure_ascii=False to dumps call.
>>> json.dumps(your_data, ensure_ascii=False)
If ensure_ascii is false, then the return value will be a
unicode instance subject to normal Python str to unicode
coercion rules in...
SQLAlchemy: cascade delete
... This is well explained in the current doc docs.sqlalchemy.org/en/rel_0_9/orm/cascades.html
– Epoc
Feb 28 '15 at 19:47
1
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Plot two histograms on single chart with matplotlib
...dom
import numpy
from matplotlib import pyplot
x = [random.gauss(3,1) for _ in range(400)]
y = [random.gauss(4,2) for _ in range(400)]
bins = numpy.linspace(-10, 10, 100)
pyplot.hist(x, bins, alpha=0.5, label='x')
pyplot.hist(y, bins, alpha=0.5, label='y')
pyplot.legend(loc='upper right')
pyplot....
GDB missing in OS X v10.9 (Mavericks)
...ered Oct 23 '13 at 23:57
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How to get position of a certain element in strings vector, to use it as an index in ints vector?
...nting to the element, simply subtract v.begin() from the iterator:
ptrdiff_t pos = find(Names.begin(), Names.end(), old_name_) - Names.begin();
Now you need to check pos against Names.size() to see if it is out of bounds or not:
if(pos >= Names.size()) {
//old_name_ not found
}
vector i...