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define() vs. const
... a static scalar (number, string or other constant like true, false, null, __FILE__), whereas define() takes any expression. Since PHP 5.6 constant expressions are allowed in const as well:
const BIT_5 = 1 << 5; // Valid since PHP 5.6 and invalid previously
define('BIT_5', 1 << 5); /...
What are the best JVM settings for Eclipse? [closed]
...clipse.platform
--launcher.defaultAction
openFile
-vm
C:/Prog/Java/jdk1.6.0_21/jre/bin/server/jvm.dll
-vmargs
-Dosgi.requiredJavaVersion=1.6
-Declipse.p2.unsignedPolicy=allow
-Xms128m
-Xmx384m
-Xss4m
-XX:PermSize=128m
-XX:MaxPermSize=384m
-XX:CompileThreshold=5
-XX:MaxGCPauseMillis=10
-XX:MaxHeapFre...
What is “:-!!” in C code?
...ld.
The macro is somewhat misnamed; it should be something more like BUILD_BUG_OR_ZERO, rather than ...ON_ZERO. (There have been occasional discussions about whether this is a confusing name.)
You should read the expression like this:
sizeof(struct { int: -!!(e); }))
(e): Compute expression e....
How much faster is Redis than mongoDB?
...is()
mongo = Connection().test
collection = mongo['test']
collection.ensure_index('key', unique=True)
def mongo_set(data):
for k, v in data.iteritems():
collection.insert({'key': k, 'value': v})
def mongo_get(data):
for k in data.iterkeys():
val = collection.find_one({'key'...
pandas dataframe columns scaling with sklearn
...ndas dataframe with mixed type columns, and I'd like to apply sklearn's min_max_scaler to some of the columns. Ideally, I'd like to do these transformations in place, but haven't figured out a way to do that yet. I've written the following code that works:
...
Calling C/C++ from Python?
...ed to provide those declaring them as extern "C"
extern "C" {
Foo* Foo_new(){ return new Foo(); }
void Foo_bar(Foo* foo){ foo->bar(); }
}
Next you have to compile this to a shared library
g++ -c -fPIC foo.cpp -o foo.o
g++ -shared -Wl,-soname,libfoo.so -o libfoo.so foo.o
And finally...
Is there a math nCr function in python? [duplicate]
...
def nCr(n,r):
f = math.factorial
return f(n) / f(r) / f(n-r)
if __name__ == '__main__':
print nCr(4,2)
In Python 3, use the integer division // instead of / to avoid overflows:
return f(n) // f(r) // f(n-r)
Output
6
...
MFC 获取当前时间的几种方法总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...ime curTime = CTime::GetCurrentTime();CString strCurTime;strCurTime.Format(_T("d d d d:d:d"), curTime...1.CTime类获取当前时间
CTime curTime = CTime::GetCurrentTime();
CString strCurTime;
strCurTime.Format(_T("d/d/d d:d:d"), curTime.GetYear(), curTime.GetMonth(), curTime.GetDay(), curTi...
Google breakpad stackwalker无法加载符号 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...Google breakpad安装好以后，按要求生成 sym，但是最终minidump_stackwalk打印出来的堆栈还是提示找不到符号。这是因为它要求符号文件有一 Google breakpad安装好以后，按要求生成.sym，但是最终 minidump_stackwalk 打印出来的堆栈还是提示...
How to convert An NSInteger to an int?
...endently of whether you are building for a 32-bit or a 64-bit system.
#if __LP64__ || TARGET_OS_EMBEDDED || TARGET_OS_IPHONE || TARGET_OS_WIN32 || NS_BUILD_32_LIKE_64
typedef long NSInteger;
#else
typedef int NSInteger;
#endif
You can use NSInteger any place you use an int without converting it....