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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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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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How can I configure my makefile for debug and release builds?
I have the following makefile for my project, and I'd like to configure it for release and debug builds. In my code, I have lots of #ifdef DEBUG macros in place, so it's simply a matter of setting this macro and adding the -g3 -gdwarf2 flags to the compilers. How can I do this?
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How to use cURL to get jSON data and decode the data?
So I have a link that returns a jSON object, and I need to have it decoded and put into variables in PHP.
6 Answers
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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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IEnumerable and Recursion using yield return
I have an IEnumerable<T> method that I'm using to find controls in a WebForms page.
8 Answers
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Extracting specific columns from a data frame
I have an R data frame with 6 columns, and I want to create a new dataframe that only has three of the columns.
10 Answers
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