Skip to main content

The layers of web platforms

It seems that the operating systems are the first layer of flatforms for building multiple applications. But operating systems are not enough for various requirements, and building applications directly upon operating systems layer is just very difficult and hard to transplant.

So, we build applications inside our internet navigators. It is the first layer of web platforms, solve a lot of cross-OS problems. Now, multiple APIs arise and become very popular, such as javascript based libraries, AJAX, Flash, Silverlight etc... Maybe we could play game like Quake 4 inside the Firefox with a 3D engine built by javascript.

There comes the next layer, which is the gadget layer. The web 2.0 websites open their API for third party developers, the typical is Facebook. Applications built on this layer could easily make use of the social networks resources of the platform itself.

Comments

Popular posts from this blog

A simple implementation of DTW(Dynamic Time Warping) in C#/python

DTW(Dynamic Time Warping) is a very useful tools for time series analysis. This is a very simple (but not very efficient) c# implementation of DTW, the source code is available at  https://gist.github.com/1966342  . Use the program as below: double[] x = {9,3,1,5,1,2,0,1,0,2,2,8,1,7,0,6,4,4,5}; double[] y = {1,0,5,5,0,1,0,1,0,3,3,2,8,1,0,6,4,4,5}; SimpleDTW dtw = new SimpleDTW(x,y); dtw.calculateDTW(); The python implementation is available at  https://gist.github.com/3265694  . from python-dtw import Dtw import math dtw = Dtw([1, 2, 3, 4, 6], [1, 2, 3, 5],           distance_func=lambda x, y: math.fabs(x - y)) print dtw.calculate() #calculate the distance print dtw.get_path() #calculate the mapping path

Install mysql-python with mariadb

mysql-python requires libmysqlclient-dev in ubuntu, but the installation of mariadb will have the lib with unmet dependenccies, so the error of "mysql_config not found" may occurred if you install mysql-python via pip. The case is that mariadb has a compatible package, if you have the ppa setup as in  http://downloads.mariadb.org/ . Just "sudo apt-get install libmariadbclient-dev".

PrefixSpan source code in python

The prefixspan is a key algorithm for mining sequential patterns. I have implemented the algorithm in Python. The algorithm is based on the following paper: Jian Pei, Jiawei Han, Senior Member, Behzad Mortazavi-asl, Jianyong Wang, Helen Pinto, Qiming Chen, Umeshwar Dayal. Mining Sequential Patterns by Pattern-Growth: The PrefixSpan Approach. IEEE Transactions on Knowledge and Data Engineering, 2004. or their conference paper You may download the source code at the following addresses: Link1