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Scala type programming resources
... time. I will try to draw parallels between programming at the value-level and programming at the type-level.
Paradigms
There are two main paradigms in type-level programming: "object-oriented" and "functional". Most examples linked to from here follow the object-oriented paradigm.
A good, fairly...
What is the purpose of class methods?
I'm teaching myself Python and my most recent lesson was that Python is not Java , and so I've just spent a while turning all my Class methods into functions.
...
Hash Map in Python
... The second example just builds a dict in the same ways as before and then copies it. The other use dict, which would be more appopriate in this context, is dict(key1=value1, key2=value2, ...) but that requires the keys to strings which are also valid Python identifiers (and internally, thi...
How to identify numpy types in python?
....g. numpy.ma.MaskedArray not a numpy enough type?
– panda-34
Mar 10 '16 at 13:02
If you want anything in numpy.* you j...
Elastic Search: how to see the indexed data
I had a problem with ElasticSearch and Rails, where some data was not indexed properly because of attr_protected. Where does Elastic Search store the indexed data? It would be useful to check if the actual indexed data is wrong.
...
How to limit the maximum value of a numeric field in a Django model?
...as various numeric fields available for use in models, e.g. DecimalField and PositiveIntegerField . Although the former can be restricted to the number of decimal places stored and the overall number of characters stored, is there any way to restrict it to storing only numbers within a certain ...
How to change Rails 3 server default port in develoment?
...t - do not edit anything in your gem path! It will influence all projects, and you will have a lot problems later...
In your project edit script/rails this way:
#!/usr/bin/env ruby
# This command will automatically be run when you run "rails" with Rails 3 gems installed from the root of your appli...
No module named _sqlite3
...sqlite-devel (or libsqlite3-dev on some Debian-based systems)
Re-configure and re-compiled Python with ./configure --enable-loadable-sqlite-extensions && make && sudo make install
Note
The sudo make install part will set that python version to be the system-wide standard, which ...
Count the number occurrences of a character in a string
...ences of substring sub in the range [start, end]. Optional arguments start and end are interpreted as in slice notation.
>>> sentence = 'Mary had a little lamb'
>>> sentence.count('a')
4
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One-liner to check whether an iterator yields at least one element?
...s at first success easily: run any((x > 100 for x in xrange(10000000))) and then run any((x > 10000000 for x in xrange(100000000))) -- the second should take much longer.
– chbrown
Apr 18 '12 at 19:53
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