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Python: fastest way to create a list of n lists
...
The probably only way which is marginally faster than
d = [[] for x in xrange(n)]
is
from itertools import repeat
d = [[] for i in repeat(None, n)]
It does not have to create a new int object in every iteration and is about 15 % faster on my machine.
Edi...
How do I focus on one spec in jasmine.js?
... its a good tip, but currently it isn't in jasmine. this is allowed by test runners like karma. for more info read on: github.com/pivotal/jasmine/pull/309
– p1100i
Aug 12 '14 at 9:08
...
Finding the source code for built-in Python functions?
...out what file a particular module or function is implemented in you can usually print the __file__ attribute. Alternatively, you may use the inspect module, see the section Retrieving Source Code in the documentation of inspect.
For built-in classes and methods this is not so straightforward since ...
What does character set and collation mean exactly?
...a symbol, the number 0 is the
encoding for 'A', and the combination
of all four letters and their
encodings is a character set.
Now, suppose that we want to compare
two string values, 'A' and 'B'. The
simplest way to do this is to look at
the encodings: 0 for 'A' and 1 for
'B'. Be...
Arduino Sketch upload issue - avrdude: stk500_recv(): programmer is not responding
...it works. I figured the packets were some attempt at a hand-shake. So basically, I solved it using Google, patience and futzing around with the board!
– hoipolloi
Jan 12 '14 at 18:16
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Can Flask have optional URL parameters?
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You can try pip install flask_optional_routes. I created a pip for the functionality you are requesting b/c I needed it as well. The code is located at: github.com/sudouser2010/flask_optional_routes.
– sudouser2010
...
What are the differences between -std=c++11 and -std=gnu++11?
...oid extensions because I don't recommend doing anything that isn't specifically defined by the Standard... but even then, "violates" is a strange and loaded term, when a lot of these extensions are, to use Standardese, just implementation-defining or specifying things that the Standard is silent on ...
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...
Real world use cases of bitwise operators [closed]
...checksums, parity, stop bits, flow control algorithms, and so on, which usually depend on the logic values of individual bytes as opposed to numeric values, since the medium may only be capable of transmitting one bit at a time.
Compression, Encryption
Both of these are heavily dependent on bitwise ...
How do I create a link using javascript?
....attr('href',desiredLink);
a.text(desiredText);
$('body').append(a);
In all the above examples you can append the anchor to any element, not just to the 'body', and desiredLink is a variable that holds the address that your anchor element points to, and desiredText is a variable that holds the te...