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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...
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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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...
JavaScript DOM remove element
I'm trying to test if a DOM element exists, and if it does exist delete it, and if it doesn't exist create it.
5 Answers
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select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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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...
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 ...
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...
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...
Syntax for if/else condition in SCSS mixin
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You could try this:
$width:auto;
@mixin clearfix($width) {
@if $width == 'auto' {
// if width is not passed, or empty do this
} @else {
display: inline-block;
width: $width;
}
}
I'm not sure of your intended result, but setting a default value should retu...