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Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
... 0 1
# 3 bar 3 1 0
# 4 bar 4 1 0
# At this point, you can select out the columns that you want.
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new keyword in method signature
...ass.
Keep in mind that creating a "new" member is not polymorphic. If you cast the object to the base type, it will not use the derived type's member.
If you have a base class:
public class BaseClass
{
public void DoSomething() { }
}
And then the derived class:
public class DerivedType : B...
Count the items from a IEnumerable without iterating?
...enumerator.MoveNext())
result++;
}
return result;
So it tries to cast to ICollection<T>, which has a Count property, and uses that if possible. Otherwise it iterates.
So your best bet is to use the Count() extension method on your IEnumerable<T> object, as you will get the bes...
Why does PHP consider 0 to be equal to a string?
... sorts out the types for you.
0 is an int, so in this case it is going to cast 'e' to an int. Which is not parsable as one and will become 0. A string '0e' would become 0 and would match!
Use ===
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Change default primary key in Eloquent
...d to make sure you set public $incrementing = false otherwise laravel will cast the field to an Integer, giving 0
class User extends Model {
protected $primaryKey = 'my_string_key';
public $incrementing = false;
}
...
Best way to convert IList or IEnumerable to Array
...omething like this:
IEnumerable query = ...;
MyEntityType[] array = query.Cast<MyEntityType>().ToArray();
If you don't know the type within that method but the method's callers do know it, make the method generic and try this:
public static void T[] PerformQuery<T>()
{
IEnumerabl...
How do I get a human-readable file size in bytes abbreviation using .NET?
... some further cleaning of his method however (unnesecary assignments & casting). Furthermore I ran a test with a negative size (when you're comparing files) while the method of humbads flawlessly processes this this Log method will throw an exception!
– IvanL
...
Redefining NULL
...es not require null pointers to be at the machine's address zero. HOWEVER, casting a 0 constant to a pointer value must result in a NULL pointer (§6.3.2.3/3), and evaluating the null pointer as a boolean must be false. This can be a bit awkward if you really do want a zero address, and NULL is not ...
What is a NullReferenceException, and how do I fix it?
... to find out where the reference is or isn't set, right-click its name and select "Find All References". You can then place a breakpoint at every found location and run your program with the debugger attached. Every time the debugger breaks on such a breakpoint, you need to determine whether you exp...
What is boxing and unboxing and what are the trade offs?
...
from C# 3.0 In a Nutshell:
Boxing is the act of casting a value
type into a reference type:
int x = 9;
object o = x; // boxing the int
unboxing is... the reverse:
// unboxing o
object o = 9;
int x = (int)o;
...