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Which data type for latitude and longitude?
...precision. 2 bytes for each group of 4 digits, plus 3 - 8 bytes overhead.
Read the fine manual about numeric types and geometric types.
The geometry and geography data types are provided by the additional module PostGIS and occupy one column in your table. Each occupies 32 bytes for a point. The...
Python multiprocessing PicklingError: Can't pickle
...
yields an error almost identical to the one you posted:
Exception in thread Thread-2:
Traceback (most recent call last):
File "/usr/lib/python2.7/threading.py", line 552, in __bootstrap_inner
self.run()
File "/usr/lib/python2.7/threading.py", line 505, in run
self.__target(*self.__ar...
What is the difference between old style and new style classes in Python?
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Interesting that you noticed in practice, I just read that this is because new-style classes, once they have found the attribute in the instance dict, have to do an additional lookup to work out whether it is a description, ie, it has a get method that needs to be invoked t...
How persistent is localStorage?
... local storage really serve difference purposes. Cookies are primarily for reading server-side, LocalStorage can only be read client-side. So the question is, in your app, who needs this data — the client or the server?
s...
How to store arrays in MySQL?
... you don't need relational databases, you can use e.g. a key-value store.
Read about database normalization, please. The golden rule is "[Every] non-key [attribute] must provide a fact about the key, the whole key, and nothing but the key.". An array does too much. It has multiple facts and it stor...
How can I troubleshoot my Perl CGI script?
...ed" or "Method not
implemented", it probably means that your script is not
readable and executable by the web server user. On flavors
of Unix, changing the mode to 755 is recommended:
chmod 755 filename. Never set a mode to 777!
Are you using use strict?
Remember that Perl automatically creates v...
How to update PATH variable permanently from Windows command line?
... modifying system PATH. It just needs a simple C++ app with a few registry reads and writes, followed by a SendMessage. Set the requestedExecutionLevel to requireAdministrator in the app manifest.
– David Heffernan
Dec 2 '11 at 15:56
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How to drop columns by name in a data frame
I have a large data set and I would like to read specific columns or drop all the others.
11 Answers
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Change default timeout for mocha
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By default Mocha will read a file named test/mocha.opts that can contain command line arguments. So you could create such a file that contains:
--timeout 5000
Whenever you run Mocha at the command line, it will read this file and set a timeout ...
What is state-of-the-art for text rendering in OpenGL as of version 4.1? [closed]
There are already a number of questions about text rendering in OpenGL, such as:
5 Answers
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