Last summer i learned python as you may know from a previous post. And this semester i used it in the Pattern Recognition course projects. I know Matlab is best suitable for them but i had no time to learn Matlab.

During the projects i learned so many useful things about python and some few tips and tricks that help writing better code. So here you are some of them ..

1- Follow Google styleguide for python http://google-styleguide.googlecode.com/svn/trunk/pyguide.html

2- sorting a dictionary

unsorteddic = {'a':5,'b':4,'c':3,'d':2,'e':1} result = sorted(unsorteddic.items(),lambda x,y: cmp(x[1],y[1]))

3- dividing a list into equal sized sub lists using lambda functions. Lambda functions are very powerful tools to use in your code.

#A:list to split, size: size of each sublist splitter = lambda A,size: [A[i:i+size]for i in range (0,len(A),size)] #in the main code, we want to divide data into 3 sub sets data = [(1,2),(3,4),(5,6),(7,8),(9,10),(11,12),(13,14),(15,16),(17,18)] triplet = len(data)/3 sublist1,sublist2,sublist3 = splitter(data,triplet)

4- using zip function to separate/combine pairs in a list, like x,y coordinates of points.

XY = [(1,2),(3,4),(5,6),(7,8),(9,10),(11,12),(13,14),(15,16),(17,18)] #separating them X,Y = zip(*XY) #combining results again recombined = zip(X,Y)

5- using list comprehension to optimize your code and save time. For this example it's better to use the last zip function (follow the Zen of Python)

XY = [(1,2),(3,4),(5,6),(7,8),(9,10),(11,12),(13,14),(15,16),(17,18)] #implementing our zip function X,Y = [XY[i][0] for i in range(0,len(XY))],[XY[i][1] for i in range(0,len(XY))] #recombining again recombined = [tuple(X[i],Y[i]) for i in range(0,len(X))]

That's most of the things i used in my projects. Ofcourse there are more but still i am a beginner. If you have any suggestion to the above code you are sure welcomed.

Python in peace

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