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Python != operation vs “is not”
...right hand side and the left hand side are the very same object. No methodcalls are done, objects can't influence the is operation.
You use is (and is not) for singletons, like None, where you don't care about objects that might want to pretend to be None or where you want to protect against object...
Correct use of Multimapping in Dapper
...ID,
CustomerName.
This makes the spliton: parameter not so useful, especially when you're not sure what order the columns are returned in. Of course you could manually specify columns...but it's 2017 and we just rarely do that anymore for basic object gets.
What we do, and it's worked great fo...
Append an object to a list in R in amortized constant time, O(1)?
...irthday. Some kind readers keep repeating any shortcomings with it, so by all means also see some of the comments below. One suggestion for list types:
newlist <- list(oldlist, list(someobj))
In general, R types can make it hard to have one and just one idiom for all types and uses.
...
计算统计特征（正态分布）函数及实例 - C/C++ - 清泛网 - 专注C/C++及内核技术
...AX_VAR;
double _ave;
//double _var;
double _sam_stdev;
double _all_stdev;
double _sum;
double _sum_2;
int _count;
double _min_v;
double _max_v;
StdevInfo()
: _ave(0.0)
//, _var(MAX_VAR)
, _sam_stdev(sqrt(MAX_VAR))
, _all_stdev(0.0)
, _sum(0.0)
...
Convert base-2 binary number string to int
... (as suggested by the >>> prompt), you don't need to use print at all. The OP's hypothetical example didn't. So it really should be identical in Python 2 and 3.
– John Y
Jul 12 '16 at 22:36
...
Calling class staticmethod within the class body?
... def stat_func():
return 42
_ANS = stat_func.__func__() # call the staticmethod
def method(self):
ret = Klass.stat_func()
return ret
As an aside, though I suspected that a staticmethod object had some sort of attribute storing the original function, I had no ...
Programmatically open new pages on Tabs
...cript you can use
window.open('page.html','_newtab');
Said that, I partially agree with Sam. You shouldn't force user to open new pages or new tab without showing them a hint on what is going to happen before they click on the link.
Let me know if it works on other browser too (I don't have a ch...
Which method performs better: .Any() vs .Count() > 0?
...le<T> sequence.
For just IEnumerable<T>, then Any() will generally be quicker, as it only has to look at one iteration. However, note that the LINQ-to-Objects implementation of Count() does check for ICollection<T> (using .Count as an optimisation) - so if your underlying data-sou...
What's the bad magic number error?
...the pyc file or trying to run a pyc from a different version of python (usually later) than your interpreter.
If they are your pyc files, just delete them and let the interpreter re-compile the py files. On UNIX type systems, that could be something as simple as:
rm *.pyc
or:
find . -name '*.py...
Is this object-lifetime-extending-closure a C# compiler bug?
...L_000e: ldloc.0
IL_000f: ldc.r8 42
IL_0018: ldc.r8 1
IL_0021: call float64 [mscorlib]System.Math::Pow(float64, float64)
IL_0026: stfld float64 ConsoleApplication1.Program/Foo/'<>c__DisplayClass1'::capturedVariable
IL_002b: ldarg.0
IL_002c: ldloc.0
IL_002d: ldftn ins...