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What are the differences between numpy arrays and matrices? Which one should I use?

...ted/numpy.matrix.html As other answers already state that you can achieve all the operations with NumPy arrays. share | improve this answer | follow | ...
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What is the preferred/idiomatic way to insert into a map?

... First of all, operator[] and insert member functions are not functionally equivalent : The operator[] will search for the key, insert a default constructed value if not found, and return a reference to which you assign a value. Obvi...
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How can I rotate an HTML 90 degrees?

... Just as a suggestion to all future readers: always place the prefixed rules before the standards definition. In this case, all browser-prefixed rules should be before the transform: rotate(90deg); rule. The reason would be that typically, you want t...
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How can I replace every occurrence of a String in a file with PowerShell?

Using PowerShell, I want to replace all exact occurrences of [MYID] in a given file with MyValue . What is the easiest way to do so? ...
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Rails raw SQL example

... and then you'd need to call values on this PG::Result object to get the results array – jobwat Mar 26 '14 at 1:00 3 ...
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Asserting successive calls to a mock method

Mock has a helpful assert_called_with() method . However, as far as I understand this only checks the last call to a method. If I have code that calls the mocked method 3 times successively, each time with different parameters, how can I assert these 3 calls with their specific parameters? ...
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How does functools partial do what it does?

...xtend(extra_args) return func(*args) return wrapper So, by calling partial(sum2, 4) you create a new function (a callable, to be precise) that behaves like sum2, but has one positional argument less. That missing argument is always substituted by 4, so that partial(sum2, 4)(2) == sum2...
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MySQL, Check if a column exists in a table with SQL

...pecific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception. ...
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How to count the number of set bits in a 32-bit integer?

...Hamming Weight', 'popcount' or 'sideways addition'. The 'best' algorithm really depends on which CPU you are on and what your usage pattern is. Some CPUs have a single built-in instruction to do it and others have parallel instructions which act on bit vectors. The parallel instructions (like x86's ...
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How to increase the vertical split window size in Vim

:vsplit (short form: :vs ) split the Vim viewport vertically. :30vs splits the viewport, making the new window 30 characters wide. Once this 30 char window is created, how would one change it's size to 31 or 29? ...