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Convert Long into Integer
...yslov the question was about Long values, not about null values. And personally I believe in rejecting null up front rather than using null in -> null out and thereby transporting null through my application. So one could also argue this is the worst answer :-)
– Sean Patric...
What's the pythonic way to use getters and setters?
...
Try this: Python Property
The sample code is:
class C(object):
def __init__(self):
self._x = None
@property
def x(self):
"""I'm the 'x' property."""
print("getter of x called")
return self._x
@x.setter
def x(self, value):
print("sette...
Merge Images Side by Side(Horizontally)
...hips with the montage utility. Montage will append each image side-by-side allowing you to adjust spacing between each image (-geometry), and the general layout (-tile).
montage [0-5].png -tile 5x1 -geometry +0+0 out.png
Other examples can be found on Montage Usage page
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JSON serialization of Google App Engine models
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There is a small mistake in the code: Where you have "output[key] = to_dict(model)" it should be: "output[key] = to_dict(value)". Besides that it's perfect. Thanks!
– arikfr
Nov 7 '09 at 22:02
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How to convert Strings to and from UTF8 byte arrays in Java
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US-ASCII is actually not a very common encoding nowadays. Windows-1252 and ISO-8859-1 (which are supersets of ASCII) are far more widespread.
– Michael Borgwardt
Oct 9 '09 at 13:26
...
How to add a 'or' condition in #ifdef
...¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|//
#ifdef CONDITION_01 //| |//
#define TEMP_MACRO //| |//
#endif //| |//
#ifdef CONDITION_02 //| |//
#define TEMP_MACRO //| |//
#endif ...
How to clear the cache in NetBeans
... me absolutely crazy, trying to track down bugs for hours that weren't actually there -- the class with the main method was not being found, and some custom exception classes were not being recognized as implementing Throwable... I just deleted the stupid cache, and now all of it works fine.
...
What's the difference between globals(), locals(), and vars()?
... the same dict each time - it's attached to the stack frame object as its f_locals attribute. The dict's contents are updated on each locals() call and each f_locals attribute access, but only on such calls or attribute accesses. It does not automatically update when variables are assigned, and assi...
Apply multiple functions to multiple groupby columns
...ion.
I recommend making a single custom function that returns a Series of all the aggregations. Use the Series index as labels for the new columns:
def f(x):
d = {}
d['a_sum'] = x['a'].sum()
d['a_max'] = x['a'].max()
d['b_mean'] = x['b'].mean()
d['c_d_prodsum'] = (x['c'] * x['d...
Converting a Java Keystore into PEM Format
...- keystore in java format.
foo.p12 - keystore in PKCS#12 format.
foo.pem - all keys and certs from keystore, in PEM format.
(This last file can be split up into keys and certificates if you like.)
Command summary - to create JKS keystore:
keytool -keystore foo.jks -genkeypair -alias foo \
...