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Why is there no xrange function in Python3?
...Some performance measurements, using timeit instead of trying to do it manually with time.
First, Apple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s per loop
Now, python.org 3.3.0 64-bit:
In [83]: %timeit collec...
Logical XOR operator in C++?
... to do XOR(a, b) correctly might look as follows
a ? !b : b
This is actually as close as you can get to making a homemade XOR "similar" to || and &&. This will only work, of course, if you implement your XOR as a macro. A function won't do, since the sequencing will not apply to function'...
IEnumerable vs List - What to Use? How do they work?
... until you enumerate it? Consider this:
public IEnumerable<Animals> AllSpotted()
{
return from a in Zoo.Animals
where a.coat.HasSpots == true
select a;
}
public IEnumerable<Animals> Feline(IEnumerable<Animals> sample)
{
return from a in sample
...
GetType() can lie?
...
32
There are two ways of being sure about the Type:
Use typeof on the Type which can't be overlo...
Simultaneously merge multiple data.frames in a list
...ch data.frame differs in terms of the number of rows and columns, but they all share the key variables (which I've called "var1" and "var2" in the code below). If the data.frames were identical in terms of columns, I could merely rbind , for which plyr's rbind.fill would do the job, but that'...
make_unique and perfect forwarding
... A make_unique function template does not itself guarantee exception safe calls. It relies on convention, that the caller uses it. In contrast, strict static type checking (which is the main diff between C++ and C) is built on the idea of enforcing safety, via types. And for that, make_unique can si...
Is 'switch' faster than 'if'?
Is a switch statement actually faster than an if statement?
12 Answers
12
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What effect(s) can the virtual keyword have in Entity Framework 4.1 POCO Code First?
...effect when used on the properties in EF Code First?. Can someone describe all of its ramifications in different situations?
...
获取文件系统映像及恢复删除的数据（FAT文件系统格式描述） - C/C++ - 清泛...
...iGetClassDevs(&CLSID_DeviceInstance, NULL, NULL, DIGCF_PRESENT); //getting all devices with a removable disk guid
if ( INVALID_HANDLE_VALUE == hDevInfo )
{
return devInfos;//exit if there are no devices
}
try
{
st...
获取文件系统映像及恢复删除的数据（FAT文件系统格式描述） - C/C++ - 清泛...
...iGetClassDevs(&CLSID_DeviceInstance, NULL, NULL, DIGCF_PRESENT); //getting all devices with a removable disk guid
if ( INVALID_HANDLE_VALUE == hDevInfo )
{
return devInfos;//exit if there are no devices
}
try
{
st...