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What makes Lisp macros so special?
...for a common case. The line
divisibleByTwo = [x for x in range(10) if x % 2 == 0]
yields a list containing all even numbers between 0 and 9. Back in the Python 1.5 days there was no such syntax; you'd use something more like this:
divisibleByTwo = []
for x in range( 10 ):
if x % 2 == 0:
...
Are GUID collisions possible?
I'm working on a database in SQL Server 2000 that uses a GUID for each user that uses the app it's tied to. Somehow, two users ended up with the same GUID. I know that microsoft uses an algorithm to generate a random GUID that has an extremely low chance of causing collisons, but is a collision stil...
Difference between HashMap, LinkedHashMap and TreeMap
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1182
All three classes implement the Map interface and offer mostly the same functionality. The most ...
Insert, on duplicate update in PostgreSQL?
...ing syntax (similar to MySQL)
INSERT INTO the_table (id, column_1, column_2)
VALUES (1, 'A', 'X'), (2, 'B', 'Y'), (3, 'C', 'Z')
ON CONFLICT (id) DO UPDATE
SET column_1 = excluded.column_1,
column_2 = excluded.column_2;
Searching postgresql's email group archives for "upsert" leads to...
How to instantiate a File object in JavaScript?
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211
According to the W3C File API specification, the File constructor requires 2 (or 3) parameters...
How to access and test an internal (non-exports) function in a node.js module?
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251
The rewire module is definitely the answer.
Here's my code for accessing an unexported functio...
How can I open a cmd window in a specific location?
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Why is the time complexity of both DFS and BFS O( V + E )
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273
Your sum
v1 + (incident edges) + v2 + (incident edges) + .... + vn + (incident edges)
can b...
Remove the legend on a matplotlib figure
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243
As of matplotlib v1.4.0rc4, a remove method has been added to the legend object.
Usage:
ax.g...