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Practical use of `stackalloc` keyword
Has anyone ever actually used stackalloc while programming in C#? I am aware of what is does, but the only time it shows up in my code is by accident, because Intellisense suggests it when I start typing static , for example.
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Difference between API and ABI
..., which takes a long integer parameter. So as a Programming Interface it's all expressed in source code. The compiler turns this into executable instructions which conform to the implementation of this language on this particular operating system. And in this case result in some low level operations...
Java HashMap performance optimization / alternative
...={99,100}) will hash to the same value as (a[]={3,1,2}, b[]={100,99}). Actually all keys k1 and k2 where sum(k1.a)==sum(k2.a) and sum(k1.b)=sum(k2.b) will result in collisions. I suggest assigning a weight to each position of the array:
hash = hash * 5381 + (c0*a[0] + c1*a[1]);
hash = hash * 5381 +...
Do you have to put Task.Run in a method to make it async?
... numbers for the sake of this example, granted, it's no processing time at all, it's just a matter of formulating an example here.
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MongoDB: Is it possible to make a case-insensitive query?
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Even with small datasets, it's not very efficient. You take a far bigger cpu hit than your query warrants, which could become an issue if you are trying to achieve scale.
As an alternative, you can store an uppercase copy and search against that. For instance, I have a User table that has a user...
How much faster is C++ than C#?
... more advanced JIT optimizations being complicated to implement, and the really cool ones are only arriving just now.
So C++ is faster, in many cases. But this is only part of the answer. The cases where C++ is actually faster, are highly optimized programs, where expert programmers thoroughly opti...
IN vs OR in the SQL WHERE Clause
...ds a much more complex evaluation process than the IN construct because it allows many conditions, not only equals like IN.
Here is a like of what you can use with OR but that are not compatible with IN:
greater. greater or equal, less, less or equal, LIKE and some more like the oracle REGEXP_LIKE...
AI2 Media Notification
...in several apps, tapping an action button triggers the associated event in all apps at the same time. This is due to the global nature of the broadcast receivers used. Solution: The intents for the action buttons are individualized with the app name. When a broadcast is received, the name is c...
memory_get_peak_usage() with “real usage”
...ent is set to true the PHP DOCS say it will get the real size of memory allocated from system. If it's false it will get the memory reported by emalloc()
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bash HISTSIZE vs. HISTFILESIZE?
... is ongoing.
HISTFILESIZE is the number of lines or commands that (a) are allowed in the history file at startup time of a session, and (b) are stored in the history file at the end of your bash session for use in future sessions.
Notice the distinction between file: on disk - and list: in memory....