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What is the difference between save and insert in Mongo DB?
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Save Vs Insert :
In your given examples, the behavior is essentially the same.
save behaves differently if it is passed with an "_id" parameter.
For save, If the document contains _id, it will upsert querying the collection on the _id field, If not, it will insert.
If a document does not...
How do I capture SIGINT in Python?
...f KeyboardInterruptException is implemented as a SIGINT handler or if it really only catches Ctrl+C presses, but either way, using a signal handler makes your intent explicit (at least, if your intent is the same as OP's). More importantly though, with a signal you don't have to wrap try-catches ar...
What is the meaning of “__attribute__((packed, aligned(4))) ”
...gned(1))) sSampleStruct;
so the above specified gcc attribute does not allow the structure padding. so the size will be 8 bytes.
If you wish to do the same for all the structures, simply we can push the alignment value to stack using #pragma
#pragma pack(push, 1)
//Structure 1
......
//Stru...
Using custom std::set comparator
...should use a functor (a class that overloads the () operator so it can be called like a function).
struct lex_compare {
bool operator() (const int64_t& lhs, const int64_t& rhs) const {
stringstream s1, s2;
s1 << lhs;
s2 << rhs;
return s1.str()...
How to get instance variables in Python?
Is there a built-in method in Python to get an array of all a class' instance variables? For example, if I have this code:
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Passing argument to alias in bash [duplicate]
...etom: If you're referring to the colors in my answer, that's done automatically by the syntax highlighter.
– Paused until further notice.
Jul 7 '14 at 5:12
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C# Sortable collection which allows duplicate keys
... Use this Comparer e.g. with SortedLists or SortedDictionaries, that don't allow duplicate keys
/// </summary>
/// <typeparam name="TKey"></typeparam>
public class DuplicateKeyComparer<TKey>
:
IComparer<TKey> where TKey : IComparable
{
#...
Accessing dict keys like an attribute?
...__init__(*args, **kwargs)
self.__dict__ = self
Some pros:
It actually works!
No dictionary class methods are shadowed (e.g. .keys() work just fine. Unless - of course - you assign some value to them, see below)
Attributes and items are always in sync
Trying to access non-existent key as an...
Using numpy to build an array of all combinations of two arrays
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It should be noted that meshgrid only works for smaller range sets, I have a large one and I get error: ValueError: maximum supported dimension for an ndarray is 32, found 69
– mikkom
Oct 20 '19 at 6:54
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How do you convert a byte array to a hexadecimal string, and vice versa?
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You're using SubString. Doesn't this loop allocate a horrible amount of string objects?
– Wim Coenen
Mar 6 '09 at 16:36
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