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Detect if a NumPy array contains at least one non-numeric value?
I need to write a function which will detect if the input contains at least one value which is non-numeric. If a non-numeric value is found I will raise an error (because the calculation should only return a numeric value). The number of dimensions of the input array is not known in advance - the fu...
C# Java HashMap equivalent
Coming from a Java world into a C# one is there a HashMap equivalent? If not what would you recommend?
7 Answers
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What are the rules for calling the superclass constructor?
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Base class constructors are automatically called for you if they have no argument. If you want to call a superclass constructor with an argument, you must use the subclass's constructor initialization list. Unlike Java, C++ supports multiple inheritance (for better or worse), so ...
Coding Practices which enable the compiler/optimizer to make a faster program
...his can be a huge help for getting around aliasing slowdowns. For example, if your code looks like
void DoSomething(const Foo& foo1, const Foo* foo2, int numFoo, Foo& barOut)
{
for (int i=0; i<numFoo, i++)
{
barOut.munge(foo1, foo2[i]);
}
}
the compiler doesn't kno...
Sending an Intent to browser to open specific URL [duplicate]
...t wondering how to fire up an Intent to the phone's browser to open an specific URL and display it.
10 Answers
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Skip download if files exist in wget?
...oading of the file. It just doesn't do anything after downloading the file if the file has already been fully retrieved. Is there anyway to prevent making the HTTP request if the file already exists? stackoverflow.com/questions/33203898/…
– ma11hew28
Oct 18 '...
Ruby, !! operator (a/k/a the double-bang) [duplicate]
...y, the only two things that evaluate to false are false (itself) and nil.
If you negate something, that forces a boolean context. Of course, it also negates it. If you double-negate it, it forces the boolean context, but returns the proper boolean value.
For example:
"hello" #-> this is a s...
How can I check whether an array is null / empty?
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There's a key difference between a null array and an empty array. This is a test for null.
int arr[] = null;
if (arr == null) {
System.out.println("array is null");
}
"Empty" here has no official meaning. I'm choosing to define empty a...
AngularJS : Why ng-bind is better than {{}} in angular?
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If you are not using ng-bind, instead something like this:
<div>
Hello, {{user.name}}
</div>
you might see the actual Hello, {{user.name}} for a second before user.name is resolved (before the data is loaded)...
Can you have if-then-else logic in SQL? [duplicate]
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You can make the following sql query
IF ((SELECT COUNT(*) FROM table1 WHERE project = 1) > 0)
SELECT product, price FROM table1 WHERE project = 1
ELSE IF ((SELECT COUNT(*) FROM table1 WHERE project = 2) > 0)
SELECT product, price FROM table1 WHER...