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Henry Huang keenhenry

4 followers · 14 following
  • Eindhoven, Noord Brabant, The Netherlands
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@keenhenry
keenhenry / equal_element_array_transformation.py
Last active August 29, 2015 14:18
Equal-element array transformation problem
#!/usr/bin/env python
"""Problem Description:
There is an array consisting of N elements, all the elements are integer numbers (can be positive, zero or negative).
A transformation step is to be applied to the array, which is detailed as follows:
Each element has to be incremented or decremented by 1 in a single step
@keenhenry
keenhenry / index.html
Last active August 29, 2015 14:26 — forked from jonnyreeves/index.html
JavaScript Class Structure using requireJS. The following code shows you how to create a Class definition in one JavaScript file and then import it for use in another; coming from an ActionScript 3 background this (and some of JavaScript specific traits)
<!DOCTYPE html>
<html>
<head>
<script data-main="usage" src="http://requirejs.org/docs/release/1.0.8/comments/require.js"></script>
</head>
<body>
<p>Check your JavaScript console for output!</p>
</body>
</head>
@keenhenry
keenhenry / DisjointSet.java
Created August 22, 2015 10:43
Disjoint Set Data Structure
public class DisjSets
{
public DisjSets( int numElements )
{
s = new int [ numElements ];
for ( int i = 0; i < s.length; ++i )
s[i] = -1;
}
@keenhenry
keenhenry / bobp-python.md
Created November 8, 2015 09:55 — forked from sloria/bobp-python.md
A "Best of the Best Practices" (BOBP) guide to developing in Python.

The Best of the Best Practices (BOBP) Guide for Python

A "Best of the Best Practices" (BOBP) guide to developing in Python.

In General

Values

  • "Build tools for others that you want to be built for you." - Kenneth Reitz
  • "Simplicity is alway better than functionality." - Pieter Hintjens
@keenhenry
keenhenry / beautiful_idiomatic_python.md
Created February 14, 2016 20:51 — forked from JeffPaine/beautiful_idiomatic_python.md
Transforming Code into Beautiful, Idiomatic Python: notes from Raymond Hettinger's talk at pycon US 2013. The code examples and direct quotes are all from Raymond's talk. I've reproduced them here for my own edification and the hopes that others will find them as handy as I have!

Transforming Code into Beautiful, Idiomatic Python

Notes from Raymond Hettinger's talk at pycon US 2013 video, slides.

The code examples and direct quotes are all from Raymond's talk. I've reproduced them here for my own edification and the hopes that others will find them as handy as I have!

Looping over a range of numbers

for i in [0, 1, 2, 3, 4, 5]:
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keenhenry / Print Python's Exception objects hierarchy
Created March 5, 2016 15:44
A small script to print out the Exception inheritance hierarchy. Useful for writing exception handling (Python 2.5+)
#!/usr/bin/env python
def classtree(cls, indent=0):
print '.' * indent, cls.__name__
for subcls in cls.__subclasses__():
classtree(subcls, indent + 3)
classtree(BaseException)
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keenhenry / latency.txt
Created March 20, 2016 10:01 — forked from jboner/latency.txt
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers
--------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@keenhenry
keenhenry / scopes.py
Created March 31, 2016 19:27
Python Scopes Quirks
#!/usr/bin/env python
# name binding always creates a name in the local scope
ng = 'a global'
def f():
# without the following commented out line, UnboundLocalError will throw
# global ng
nl = 2
print ng, nl
ng = 3
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keenhenry / script.bash
Created April 16, 2016 20:04 — forked from jiaaro/script.bash
Embed Python in a bash script
#!/bin/bash
export FOO=100
python - <<END
import os
print "foo:", os.environ['FOO']
END
@keenhenry
keenhenry / mkdir_p.py
Last active October 29, 2016 16:54
The implementation of `$ mkdir -p path` in Python: http://stackoverflow.com/questions/600268/mkdir-p-functionality-in-python
#!/usr/bin/env python
# -*- coding: utf-8 -*-
from __future__ import print_function
import errno
import os
def mkdir_p(path):
try: