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Pandas: drop a level from a multi-level column index?
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@yoonghm It is there, you are probably just calling it on columns that don't have a multi-index
– matt harrison
Dec 18 '18 at 14:59
1
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Hyphen, underscore, or camelCase as word delimiter in URIs?
...designing an HTTP-based API for an intranet app. I realize it's a pretty small concern in the grand scheme of things, but: should I use hyphens, underscores, or camelCase to delimit words in the URIs?
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Glorified classes in the Java language
... lot of different answers, so I thought it would be useful to collect them all (and add some):
Classes
AutoBoxing classes - the compiler only allows for specific classes
Class - has its own literals (int.class for instance). I would also add its generic typing without creating new instances.
Stri...
Specifying an Index (Non-Unique Key) Using JPA
...Table;
@Entity
@Table(name = "region",
indexes = {@Index(name = "my_index_name", columnList="iso_code", unique = true),
@Index(name = "my_index_name2", columnList="name", unique = false)})
public class Region{
@Column(name = "iso_code", nullable = false)
priva...
Relative URL to a different port number in a hyperlink?
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edited Nov 23 '18 at 20:32
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111 silver badge
answered May 16 '11 at 10:56
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JavaScript, elegant way to check nested object properties for null/undefined [duplicate]
...e of using the app this gets populated. Let's say somwhere, after an AJAX call or something i do this:
4 Answers
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Is it possible to get the iOS 5.1 SDK for Xcode 4.2 on Snow Leopard?
...ered Mar 8 '12 at 6:26
Mick MacCallumMick MacCallum
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C-like structures in Python
...uct(NamedTuple):
foo: str
bar: int
baz: list
qux: User
my_item = MyStruct('foo', 0, ['baz'], User('peter'))
print(my_item) # MyStruct(foo='foo', bar=0, baz=['baz'], qux=User(name='peter'))
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MySQL Orderby a number, Nulls last
... tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A good reference is here http://troels.arvin.dk/db/rdbms#select-order_by
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How do I inspect the view hierarchy in iOS?
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I've got: error: cannot find interface declaration for '$__lldb_objc_class' any ideas? (lldb) po [[UIWindow keyWindow] recursiveDescription] error: cannot find interface declaration for '$__lldb_objc_class' error: cannot find interface declaration for '$__lldb_objc_class' error:...