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Thread pooling in C++11
... can help:
1) Start with maximum number of threads a system can support:
int Num_Threads = thread::hardware_concurrency();
2) For an efficient threadpool implementation, once threads are created according to Num_Threads, it's better not to create new ones, or destroy old ones (by joining). Ther...
Split data frame string column into multiple columns
...ing columns will have correct types and improve performance by adding type.convert and fixed arguments (since "_and_" isn't really a regex)
setDT(before)[, paste0("type", 1:2) := tstrsplit(type, "_and_", type.convert = TRUE, fixed = TRUE)]
...
How to read a file without newlines?
...t would help in some circumstances, on my system \r\n line endings are not converted to \n, whether read as text or binary, so os.linesep would work where \n does not. But splitlines is clearly the better choice, in the case you mention where the file does not match the os. Really I mostly mentioned...
Multiple cases in switch statement
...red Aug 1 '10 at 13:29
Carlos QuintanillaCarlos Quintanilla
11.1k33 gold badges1919 silver badges2424 bronze badges
...
What does “Memory allocated at compile time” really mean?
...ed inside the process memory map.
For example, consider a global array:
int array[100];
The compiler knows at compile-time the size of the array and the size of an int, so it knows the entire size of the array at compile-time. Also a global variable has static storage duration by default: it is...
How does virtual inheritance solve the “diamond” (multiple inheritance) ambiguity?
... 1 instance of the base A class not 2.
Your type D would have 2 vtable pointers (you can see them in the first diagram), one for B and one for C who virtually inherit A. D's object size is increased because it stores 2 pointers now; however there is only one A now.
So B::A and C::A are the sam...
How to detect shake event with android?
...
From the code point of view, you need to implement the SensorListener:
public class ShakeActivity extends Activity implements SensorListener
You will need to acquire a SensorManager:
sensorMgr = (SensorManager) getSystemService(SENSOR_SE...
POST request via RestTemplate in JSON
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Can Spring use the message converters to automatically convert the Java Object to json like it did in Restful API with RestTemplate?
– fall
Aug 10 '17 at 10:21
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When should I use UNSIGNED and SIGNED INT in MySQL?
When should I use UNSIGNED and SIGNED INT in MySQL ?
What is better to use or this is just personal prefernce ?
Because I've seen it used like this;
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Entity Framework Code First - two Foreign Keys from same table
...
Try this:
public class Team
{
public int TeamId { get; set;}
public string Name { get; set; }
public virtual ICollection<Match> HomeMatches { get; set; }
public virtual ICollection<Match> AwayMatches { get; set; }
}
public class Match
...