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What is “entropy and information gain”?
...d male or female, given the example that reached the node. We calculate it
based on the number of male and female classes at the node.
Entropy on the other hand is a measure of impurity (the opposite). It is defined for a binary class with values a/b as:
Entropy = - p(a)*log(p(a)) - p(b)*log(p(b))...
Struct constructor: “fields must be fully assigned before control is returned to the caller.”
...;
}
}
By calling :this() from your constructor declaration you let the base ValueType class initialize all the backing fields for the automatic properties. We cannot do it manually on our constructor because we don't have access to the backing field of an automatic property.
ValueType is the bas...
Difference between ProcessBuilder and Runtime.exec()
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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...
UICollectionView current visible cell index
...ndexPath);
}
}
Update to Swift 5:
func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
for cell in yourCollectionView.visibleCells {
let indexPath = yourCollectionView.indexPath(for: cell)
print(indexPath)
}
}
...
Add data annotations to a class generated by entity framework
...1}partial class {2}{3}{4}",
Accessibility.ForType(entity),
_code.SpaceAfter(_code.AbstractOption(entity)),
_code.Escape(entity),
_code.StringBefore(" : ", _typeMapper.GetTypeName(entity.BaseType)),
stringsToMatch.Any(o => _code.Escape(entity).Contains(o.Key...
Repeat a task with a time delay?
...er());
private Runnable mStatusChecker;
private int UPDATE_INTERVAL = 2000;
/**
* Creates an UIUpdater object, that can be used to
* perform UIUpdates on a specified time interval.
*
* @param uiUpdater A runnable containing the update ro...
Is Python strongly typed?
...stom type, you can make it implicitly convert anything to a number:
def to_number(x):
"""Try to convert function argument to float-type object."""
try:
return float(x)
except (TypeError, ValueError):
return 0
class Foo:
def __init__(self, number):
self....
How to print the contents of RDD?
....
// For implicit conversion from RDD to DataFrame
import spark.implicits._
fruits = sc.parallelize([("apple", 1), ("banana", 2), ("orange", 17)])
// convert to DF then show it
fruits.toDF().show()
This will show the top 20 lines of your data, so the size of your data should not be an issue.
+...
How do you manage databases in development, test, and production?
...
Name your databases as follows - dev_<<db>> , tst_<<db>> , stg_<<db>> , prd_<<db>> (Obviously you never should hardcode db names
Thus you would be able to deploy even the different type of db's on same physical ...
system(“pause”); - Why is it wrong?
...utable named "pause"!)
Simply write your own "Pause()" function that uses _getch. OK, sure, _getch is platform dependent as well (note: it's defined in "conio.h") - but it's much nicer than system() if you are developing on Windows and it has the same effect (though it is your responsibility to pro...