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Combining two Series into a DataFrame in pandas
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this actually avoids copying too (as compared to the dict solution)
– Jeff
Aug 5 '13 at 16:27
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Find intersection of two nested lists?
... 3 filter returns an iterable instead of list, so you need to wrap filter calls with list():
c3 = [list(filter(lambda x: x in c1, sublist)) for sublist in c2]
Explanation:
The filter part takes each sublist's item and checks to see if it is in the source list c1.
The list comprehension is exec...
No route matches [GET] /assets
...nment. I ran RAILS_ENV=production rake assets:precompile which generated all of my assets in /public/assets. The problem is that when I start my app w/ RAILS_ENV=production rails s thin I get:
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What's wrong with nullable columns in composite primary keys?
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Primary keys are for uniquely identifying rows. This is done by comparing all parts of a key to the input.
Per definition, NULL cannot be part of a successful comparison. Even a comparison to itself (NULL = NULL) will fail. This means a key containing NULL would not work.
Additonally, NULL is al...
How to remove part of a string? [closed]
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If you're specifically targetting "11223344", then use str_replace:
// str_replace($search, $replace, $subject)
echo str_replace("11223344", "","REGISTER 11223344 here");
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How does the @property decorator work in Python?
...is just syntactic sugar; the syntax:
@property
def foo(self): return self._foo
really means the same thing as
def foo(self): return self._foo
foo = property(foo)
so foo the function is replaced by property(foo), which we saw above is a special object. Then when you use @foo.setter(), what you ...
Ideal Ruby project structure
...pname folder because most libraries are in the appname namespace.
Additionally, if you try running the command newgem --simple [projectname] that'll quickly generate a scaffold for you with just the bare essentials for a Ruby project (and by extension a Ruby Gem). There are other tools which do thi...
UIWebView open links in Safari
...h reference to the answer and comments below.
– Toby Allen
Mar 23 '11 at 22:08
How to go back to the application once ...
Node.js app can't run on port 80 even though there's no other process blocking the port
I'm running an instance of Debian on Amazon EC2 with Node.js installed. If I run the code below:
9 Answers
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sqlalchemy unique across multiple columns
... declares those in the table definition, or if using declarative as in the __table_args__:
# version1: table definition
mytable = Table('mytable', meta,
# ...
Column('customer_id', Integer, ForeignKey('customers.customer_id')),
Column('location_code', Unicode(10)),
UniqueConstraint...