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Why were pandas merges in python faster than data.table merges in R in 2012?
I recently came across the pandas library for python, which according to this benchmark performs very fast in-memory merges. It's even faster than the data.table package in R (my language of choice for analysis).
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Explanation of strong and weak storage in iOS5
I am new to iOS5 development and using objective-c. I have trouble understanding the difference between strong and weak storage. I have read the documentation and other SO questions, but they all sound identical to me with no further insight.
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Is file append atomic in UNIX?
In general, what can we take for granted when we append to a file in UNIX from multiple processes? Is it possible to lose data (one process overwriting the other's changes)? Is it possible for data to get mangled? (For example, each process is appending one line per append to a log file, is it po...
Why does ContentResolver.requestSync not trigger a sync?
I am trying to implement the Content-Provider-Sync Adapter pattern as discussed at Google IO - slide 26. My content provider is working, and my sync works when I trigger it from the Dev Tools Sync Tester application, however when I call ContentResolver.requestSync(account, authority, bundle) from ...
Why do x86-64 instructions on 32-bit registers zero the upper part of the full 64-bit register?
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Why does git perform fast-forward merges by default?
Coming from mercurial, I use branches to organize features.
Naturally, I want to see this work-flow in my history as well.
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Why does my application spend 24% of its life doing a null check?
I've got a performance critical binary decision tree, and I'd like to focus this question on a single line of code. The code for the binary tree iterator is below with the results from running performance analysis against it.
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Difference between rake db:migrate db:reset and db:schema:load
The difference between rake db:migrate and rake db:reset is pretty clear in my head. The thing which I don't understand is how rake db:schema:load different from the former two.
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Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
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classical inheritance vs prototypal inheritance in javascript
I have googled so many links and can't get good idea about the difference between classical inheritance and prototypal inheritance?
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