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Difference between map, applymap and apply methods in Pandas
...rame’s apply method does exactly this:
In [116]: frame = DataFrame(np.random.randn(4, 3), columns=list('bde'), index=['Utah', 'Ohio', 'Texas', 'Oregon'])
In [117]: frame
Out[117]:
b d e
Utah -0.029638 1.081563 1.280300
Ohio 0.647747 0.831136 -1.549481
Tex...
Are C++ enums signed or unsigned?
Are C++ enums signed or unsigned? And by extension is it safe to validate an input by checking that it is = your min value (assuming you started at 0 and incremented by 1)?
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Under what circumstances are linked lists useful?
... with a single CAS (+retries).
In a modern GC-d environment - such as Java and .NET - the ABA problem can easily be avoided.
Just wrap items you add in freshly created nodes and do not reuse those nodes - let the GC do its work.
The page on the ABA problem also provides the implementation of a lock...
“tag already exists in the remote" error after recreating the git tag
...o get everyone who already has the "wrong" tag to delete their "wrong tag" and replace it with the new "right tag".
Testing in Git 2.10/2.11 shows that retaining the old tag is the default behavior for clients running git fetch, and updating is the default behavior for clients running git fetch --t...
What are rvalues, lvalues, xvalues, glvalues, and prvalues?
... began with the move semantics. Once we have expressions that can be moved and not copied, suddenly easy to grasp rules demanded distinction between expressions that can be moved, and in which direction.
From what I guess based on the draft, the r/l value distinction stays the same, only in the con...
What is the difference between Left, Right, Outer and Inner Joins?
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Simple Example: Lets say you have a Students table, and a Lockers table. In SQL, the first table you specify in a join, Students, is the LEFT table, and the second one, Lockers, is the RIGHT table.
Each student can be assigned to a locker, so there is a LockerNumber column in...
What is the best Distributed Brute Force countermeasure?
...t is no secret that I am implementing an auth+auth system for CodeIgniter, and so far I'm winning (so to speak). But I've run into a pretty non-trivial challenge (one that most auth libraries miss entirely, but I insist on handling it properly): how to deal intelligently with large-scale, distribut...
What does ||= (or-equals) mean in Ruby?
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This question has been discussed so often on the Ruby mailing-lists and Ruby blogs that there are now even threads on the Ruby mailing-list whose only purpose is to collect links to all the other threads on the Ruby mailing-list that discuss this issue.
Here's one: The definitive list of ||= ...
What is the role of the bias in neural networks? [closed]
I'm aware of the gradient descent and the back-propagation algorithm. What I don't get is: when is using a bias important and how do you use it?
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How to read the output from git diff?
The man page for git-diff is rather long, and explains many cases which don't seem to be necessary for a beginner. For example:
...