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How do I check if a list is empty?
... Part 1
The "pythonic" way fails with NumPy arrays because NumPy tries to cast the array to an array of bools, and if x tries to evaluate all of those bools at once for some kind of aggregate truth value. But this doesn't make any sense, so you get a ValueError:
>>> x = numpy.array([0,1]...
Difference between decimal, float and double in .NET?
...a double/float.
Decimals and Floats/Doubles cannot be compared without a cast whereas Floats and Doubles can. Decimals also allow the encoding or trailing zeros.
float flt = 1F/3;
double dbl = 1D/3;
decimal dcm = 1M/3;
Console.WriteLine("float: {0} double: {1} decimal: {2}", flt, dbl, dcm);
Res...
How to strip all non-alphabetic characters from string in SQL Server?
...nstead of NVARCHAR within his function otherwise, your system will need to cast the string values from VARCHAR to NVARCHAR before it can perform the function which is more expensive. Even with those changes your function still might be faster, but those are a few examples I can see where his functi...
Checking for empty arrays: count vs empty
...
Alternatively, you can cast the variable as a boolean (implicitly or explicitly):
if( $value )
{
// array is not empty
}
if( (bool) $value )
{
// array is still not empty
}
This method does generate an E_NOTICE if the variable is not define...
How does a language expand itself? [closed]
I am learning C++ and I've just started learning about some of Qt 's capabilities to code GUI programs. I asked myself the following question:
...
How do I unit test web api action method when it returns IHttpActionResult?
...
Time to resurrect a dead question
The current answers all rely on casting the response object to a known type. Unfortunately, the responses do not seem to have a useable hierarchy or implicit conversion path for this to work without intimate knowledge of the controller implementation. Consi...
What is the difference between an int and an Integer in Java and C#?
... you can access methods on the heap object directly, but in C# you need to cast it back to an int, which will create another copy. Thus, the object on the heap cannot easily be changed in C# without creating a new boxed copy of a new int value. (Ugh, this paragraph doesn't read all that easily.)
...
When is it appropriate to use UDP instead of TCP? [closed]
Since TCP guarantees packet delivery and thus can be considered "reliable", whereas UDP doesn't guarantee anything and packets can be lost. What would be the advantage of transmitting data using UDP in an application rather than over a TCP stream? In what kind of situations would UDP be the better c...
What is the instanceof operator in JavaScript?
...ript, esp. for some who are used to a language that requires e.g. explicit casting to alter a variable type. As you pointed out, it's very easy to change the type from e.g. primitive int to primitive string.
– moey
Oct 18 '12 at 23:51
...
How to store arrays in MySQL?
... AS pfs_person_name,
cast(concat('[', group_concat(json_quote(fruit_name) ORDER BY fruit_name SEPARATOR ','), ']') as json) AS pfs_fruit_name_array
FROM
person
INNER JOIN person_fruit
ON person.person_id = person_fruit.pf_person
...