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pandas GroupBy columns with NaN (missing) values
...n the Missing Data section of the docs:
NA groups in GroupBy are automatically excluded. This behavior is consistent with R, for example.
One workaround is to use a placeholder before doing the groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fil...
Globally catch exceptions in a WPF application?
...ication where parts of it may throw exceptions at runtime. I'd like to globally catch any unhandled exception and log them, but otherwise continue program execution as if nothing happened (kinda like VB's On Error Resume Next ).
...
Visual Studio immediate window command for Clear All
... you can use >cls, which is a predefined command alias to >Edit.ClearAll.
The MSDN article lists all predefined aliases and you can define your own, too. (For VS 2010 and earlier, custom aliases are described in a separate article, though.) Scanning through, there's a whole slew of them, some...
'UserControl' constructor with parameters in C#
Call me crazy, but I'm the type of guy that likes constructors with parameters (if needed), as opposed to a constructor with no parameters followed by setting properties. My thought process: if the properties are required to actually construct the object, they should go in the constructor. I get two...
Does Go have “if x in” construct similar to Python?
...ion without separate methods for every single type
– Allen
May 13 '15 at 4:33
29
It could be done...
How can I add or update a query string parameter?
... @JarónBarends - Tweak value check to check against undefined and null to allow setting 0 values
Third Update
There was a bug where removing a querystring variable directly before a hashtag would lose the hashtag symbol which has been fixed
Fourth Update
Thanks @rooby for pointing out a regex o...
In Eclipse, what can cause Package Explorer “red-x” error-icon when all Java sources compile without
I'm using Eclipse for Java development. All my sources compile fine and the resulting application compiles fine. However, I keep getting an "red-x" error notification in the Package Explorer.
...
@UniqueConstraint annotation in Java
...
@Entity
@Table(uniqueConstraints={@UniqueConstraint(columnNames = {"id_1" , "id_2"})})
public class class_name {
@Id
@GeneratedValue
public Long id;
@NotNull
public Long id_1;
@NotNull
public Long id_2;
}
Hope it helped.
...
Foreign keys in mongo?
...his:
class Student
include Mongoid::Document
field :name
embeds_many :addresses
embeds_many :scores
end
class Address
include Mongoid::Document
field :address
field :city
field :state
field :postalCode
embedded_in :student
end
class Score
include Mongoi...
Java FileReader encoding issue
...to a string, but I found the result is wrongly encoded and not readable at all.
6 Answers
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