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Getting value of public static final field/property of a class in Java via reflection
...t(null);
Exception handling is left as an exercise for the reader.
Basically you get the field like any other via reflection, but when you call the get method you pass in a null since there is no instance to act on.
This works for all static fields, regardless of their being final. If the field ...
What do the terms “CPU bound” and “I/O bound” mean?
...U (doing calculations). A program that computes new digits of π will typically be CPU-bound, it's just crunching numbers.
A program is I/O bound if it would go faster if the I/O subsystem was faster. Which exact I/O system is meant can vary; I typically associate it with disk, but of course networ...
undefined reference to boost::system::system_category() when compiling
...raries. I have the 1.46-dev Boost libraries from the Ubuntu Repository installed, but I get an error when compiling the program.
...
String formatting: % vs. .format vs. string literal
...ated. And Python, not being a lazy language, evaluates expressions before calling functions, so in your log.debug example, the expression "some debug info: %s"%some_infowill first evaluate to, e.g. "some debug info: roflcopters are active", then that string will be passed to log.debug().
...
How do you express binary literals in Python?
... memory.
Note that leading zeros in a non-zero decimal number are not allowed.
This is for disambiguation with C-style octal literals, which Python
used before version 3.0.
Some examples of integer literals:
7 2147483647 0o177 0b100110111
3 7922816251...
check if variable is dataframe
...rame
Yes: isinstance(x, pd.DataFrame)
And don't even think about
if obj.__class__.__name__ = 'DataFrame':
expect_problems_some_day()
isinstance handles inheritance (see What are the differences between type() and isinstance()?). For example, it will tell you if a variable is a string (eithe...
mfc 按钮变成了非xp风格、界面变成windows经典样式的原因总结 - C/C++ - 清...
...xp风格 xp风格stdafx.h中添加：#ifdef _UNICODE#if defined _M_IX86#pragma co...首先看一下xp风格与非xp风格：
非xp风格 xp风格
stdafx.h中添加：
#ifdef _UNICODE
#if defined _M_IX86
#pragma comment(lin...
Get selected subcommand with argparse
...s:
>>> parser = argparse.ArgumentParser()
>>> parser.add_argument('-g', '--global')
>>> subparsers = parser.add_subparsers(dest="subparser_name") # this line changed
>>> foo_parser = subparsers.add_parser('foo')
>>> foo_parser.add_argument('-c', '--count...
How does SIGINT relate to the other termination signals such as SIGTERM, SIGQUIT and SIGKILL?
On POSIX systems, termination signals usually have the following order (according to many MAN pages and the POSIX Spec):
6 ...
Scala best way of turning a Collection into a Map-by-key?
...unction seems to assume that I already have a tuple (m,s), which I don't really get
– oxbow_lakes
Mar 24 '09 at 22:33
2
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