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Design Patterns: Abstract Factory vs Factory Method
...ctory as it can create various related database objects such as connection and command objects.
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Get unique values from a list in python [duplicate]
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mylist = ['nowplaying', 'PBS', 'PBS', 'nowplaying', 'job', 'debate', 'thenandnow']
myset = set(mylist)
print(myset)
If you use it further as a list, you should convert it back to a list by doing:
mynewlist = list(myset)
Another possibility, probably faster would be to use a set from the beginn...
RuntimeWarning: invalid value encountered in divide
...is trying to "divide by zero" or "divide by NaN". If you are aware of that and don't want it to bother you, then you can try:
import numpy as np
np.seterr(divide='ignore', invalid='ignore')
For more details see:
http://docs.scipy.org/doc/numpy/reference/generated/numpy.seterr.html
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What are the differences between Chosen and Select2?
Chosen and Select2 are the two more popular libraries for extending selectboxes.
11 Answers
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How do I search within an array of hashes by hash values in ruby?
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Oh! You were the first one! Deleting my answer and +1.
– Milan Novota
Feb 11 '10 at 14:13
22
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Is it possible for a computer to “learn” a regular expression by user-provided examples?
...ton, it is possible to learn some regular expressions by a program. Kearns and Valiant show some cases where it is not possible to learn a finite automaton. A related problem is learning hidden Markov Models, which are probabilistic automata that can describe a character sequence. Note that most mod...
Combining multiple git repositories
...-)
$ cp -r phd phd-backup
Move the content of phd/code to phd/code/code, and fix the history so that it looks like it has always been there (this uses git's filter-branch command):
$ cd phd/code
$ git filter-branch --index-filter \
'git ls-files -s | sed "s#\t#&code/#" |
GIT_INDEX_FI...
What is the best way to force yourself to master vi? [closed]
...f the misconceptions about vi, as well as explaining why it's a good idea (and why it's been very popular for the last 30 years+). The same guy also has a great set of graphical cheat sheets that teach the basics a few bits at a time.
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I need to store postal codes in a database. How big should the column be?
...n it?
If the initial version of your application is going to support US and Canadian addresses (which I'm inferring from the fact that you call out those sizes in your question), I'd declare the field as VARCHAR2(9) (or VARCHAR2(10) if you intend to store the hyphen in ZIP+4 fields). Even lookin...
How can I write a regex which matches non greedy? [duplicate]
...o a trick you can do to work around this: Since \s means "any whitespace", and "\S" means "any non-whitespace", [\s\S] will match ANY character (like ".", but including new line)! Similarly, you could use [\d\D], or [\w\W]. This can be quite a handy little "hack", and it certainly a very useful tric...