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Filtering a list based on a list of booleans
...rue, False, True, False]
>>> %timeit list(compress(list_a, fil))
100000 loops, best of 3: 2.58 us per loop
>>> %timeit [i for (i, v) in zip(list_a, fil) if v] #winner
100000 loops, best of 3: 1.98 us per loop
>>> list_a = [1, 2, 4, 6]*100
>>> fil = [True, False,...
JPA: How to have one-to-many relation of the same Entity type
... the relationship is the same. The general case is detailed in Section 2.10.2 of the JPA 2.0 spec.
Here's a worked example. First, the entity class A:
@Entity
public class A implements Serializable {
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
@ManyToOne
...
How to use RSpec's should_raise with any kind of exception?
...
380
expect { some_method }.to raise_error
RSpec 1 Syntax:
lambda { some_method }.should raise_err...
UIView with rounded corners and drop shadow?
...nd drop shadow to v, a UIView:
// border radius
[v.layer setCornerRadius:30.0f];
// border
[v.layer setBorderColor:[UIColor lightGrayColor].CGColor];
[v.layer setBorderWidth:1.5f];
// drop shadow
[v.layer setShadowColor:[UIColor blackColor].CGColor];
[v.layer setShadowOpacity:0.8];
[v.layer setSh...
When do I use fabs and when is it sufficient to use std::abs?
...
answered Jun 25 '10 at 13:06
Mike SeymourMike Seymour
230k2424 gold badges396396 silver badges602602 bronze badges
...
Re-entrant locks in C#
...
150
No, not as long as you are locking on the same object. The recursive code effectively already h...
What's the difference between Html.Label, Html.LabelFor and Html.LabelForModel
...
110
Html.Label gives you a label for an input whose name matches the specified input text (more spec...
How to create the branch from specific commit in different branch
...where your HEAD is.
What you are doing:
git checkout dev
git branch test 07aeec983bfc17c25f0b0a7c1d47da8e35df7af8
First, you set your HEAD to the branch dev,
Second, you start a new branch on commit 07aeec98. There is no bb.txt at this commit (according to your github repo).
If you want to st...
Is it necessary to explicitly remove event handlers in C#
... Console.WriteLine("~Publisher");
Console.WriteLine("Foo==null ? {0}", Foo == null);
}
public event EventHandler Foo;
}
public class Subscriber
{
~Subscriber()
{
Console.WriteLine("~Subscriber");
}
public void FooHandler(object sender, EventArgs e) {}
}
p...