There really isn’t such a mathematical term – it was introduced at the latest Al Zimmermann’s Programming Contests and is defined in the contest rules (at azpcs.net – site should be back up around mid December January, a replacement is currently up at trdb.org ). As I’m participating in this contest and have created some …
Needed to convert a one dimensional array to a two dimensional numpy matrix and then add a row vector to the end of the matrix. import numpy array1d = range(10,100) array2d = [array1d[i:i + 10] for i in range(0, len(array1d), 10)] newline = [88 for i in range(1,11)] m = numpy.matrix(array2d) m_extended = numpy.vstack([m, newline])
I needed to convert a JSON hierarchy to an HTML bullet hierarchy and all the solutions I found on the Web were overkill. Enjoy. <!DOCTYPE html> <head> <script> var g_tree = { "1":{ "11":{ "111":{ "option1":1, …
To Install the atom editor for Linux (taken from here): $ sudo add-apt-repository ppa:webupd8team/atom $ sudo apt-get update $ sudo apt-get install atom I needed syntax highlighting for Lua. My suggestion is: Start atom, press <Ctrl><Shift>P Type: install packages Select ‘Settings View: Install Packages’ Search for language-lua package install the language-lua package You should get …
Got the solution from here: Shut down the guest machine Select the Ubuntu 14.04 virtual machine and click the Settings button Select the ‘Display’ item from the list on the left In the Video tab on the right, check the ‘Enable 3D Video Acceleration’ option Select the ‘Storage’ item from the list on the left …
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Assuming your Ubuntu guest username is USERNAME: Make sure you have already installed the VirtualBox Guest Additions in the Ubuntu guest machine From the Ubuntu guest: sudo adduser USERNAME vboxsf Using the VirtualBox UI (Devices->Shared Folder Settings…) add the folder in the hosting machine that you wish to share. Restart the Ubuntu guest! (wasted too …
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I needed to understand the protocol between an iPhone application and the server. There was no written documentation and the company that owned the application wanted me to build something based on the protocol. The first thing I tried was using squid as a proxy to intercept the protocol between the iPhone application and the …
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If you need to import a very large SQL dump file to MySQL, the following should speed things up considerably: At the begining of the SQL dump file, add: SET autocommit=0; SET unique_checks=0; SET foreign_key_checks=0; and at the end: COMMIT; Then proceed as usual with the import, i.e mysql> source myfile.sql
If you mount the guest additions and see a warning about missing kernel headers, and the additions don’t seem to work, and then after trying to launch the guest additions CD again you get VERR_PDM_MEDIA_LOCKED error and everything starts going downhill from there – this is the solution that worked for me: 1. Reinstall Ubuntu …
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Update Dec 5th 2014: Fixed and updated the code. Update Mar 9th 2017: Updated the code to handle null values in CSV. This is a simplified Lua script to read and write CSV files. It assumes the separator character does not exist in one of the values. I don’t know why I couldn’t find a …