Python : Data Encapsulation The following table shows the different behaviour: Name Notation Behaviour name Public Can be accessed from inside and outside _name Protected Like a public member, but they shouldn't be directly accessed from outside. __n…
Coursera课程<Python Data Structures> 密歇根大学 Charles Severance Week6 Tuple 10 Tuples 10.1 Tuples Are Like Lists 元组是另外一种序列,它的方法和list挺像的.它的元素也是从0开始计数. >>> x = ('Glenn', 'Sally', 'Joseph') >>> print(x[2]) Joseph >>> y = (1, 9, 2)…
All Objective-C programs are composed of the following two fundamental elements: Program statements (code): This is the part of a program that performs actions and they are called methods. Program data: The data is the information of the program whic…
Coursera课程<Python Data Structures> 密歇根大学 Charles Severance Week4 List 8.2 Manipulating Lists 8.2.1 Concatenating Lists Using + 使用"+"可以把存在的两个list加在一起.如: >>> a = [1, 2, 3] >>> b = [4, 5, 6] >>> c = a + b >>&g…
原文:http://www.jianshu.com/p/94516a58314d Dataset transformations| 数据转换 Combining estimators|组合学习器 Feature extration|特征提取 Preprocessing data|数据预处理 1 Dataset transformations scikit-learn provides a library of transformers, which may clean (see Preproce…
User-defined functions from:https://campus.datacamp.com/courses/python-data-science-toolbox-part-1/writing-your-own-functions?ex=1 Strings in Python To assign the string company = 'DataCamp' You've also learned to use the operations + and * with stri…
In the former article "Data Preparation by Pandas and Scikit-Learn", we discussed about a series of steps in data preparation. Scikit-Learn provides the Pipeline class to help with such sequences of transformations. The Pipeline constructor take…
In this article, we dicuss some main steps in data preparation. Drop Labels Firstly, we drop labels for train set. Here we use drop() method in Pandas library. housing = strat_train_set.drop("median_house_value", axis=1) # drop labels for traini…
import numpy as np import matplotlib.pyplot as plt def is_outlier(points, threshold=3.5): if len(points.shape) == 1: points = points[:, None] # Find the median number of points median = np.median(points, axis=0) diff = np.sum((points - median)**2, ax…
import numpy as np import matplotlib.pyplot as plt import seaborn; seaborn.set() rand = np.random.RandomState(42) x = rand.rand(10,2) #数组 plt.scatter(x[:,0],x[:,1],s=100) #数组第一列为横坐标,第二列为纵坐标 s=100:散点大小 plt.show() any list of dictionaries can be made i…
Before you can plot anything, you need to specify which backend Matplotlib should use. The simplest option is to use Jupyter’s magic command %matplotlib inline. This tells Jupyter to set up Matplotlib so it uses Jupyter’s own backend. Scatter Plot ho…
Pandas is a great lib to process BIg Data. 1) pandas.pivot_table(data,values=None,columns=None,aggfunc=func) func can be any function in python 2) pandas.merge(left,right,hpw='inner') combine left with right based on the inner columns. 3) pandas.read…
From: http://interactivepython.org/courselib/static/pythonds/Introduction/GettingStartedwithData.html Built-in Collection Data Types Python has a number of very powerful built-in collection classes. Lists, strings, and tuples are ordered collections…
A Complete Tutorial to Learn Data Science with Python from Scratch Introduction It happened few years back. After working on SAS for more than 5 years, I decided to move out of my comfort zone. Being a data scientist, my hunt for other useful tools w…
In this chapter I present classes to represent playing cards, decks of cards, and poker hands.If you don't play poker, you can read about it at http://en.wikipedia.org/wiki/Poker, but you don’t have to; I’ll tell you what you need to know for the exe…
7 Must Read Python Books I started learning Python just two years ago. Coming from a C++ and Java background, it was easy to pick up the basic language features, but I wanted to learn more. What I did was order all the Python books that had good rati…
写在前面的话:关于数据结构与算法讲解的书籍很多,但是用python语言去实现的不是很多,最近有幸看到一本这样的书籍,由Brad Miller and David Ranum编写的<Problem Solving with Algorithms and Data Structures Using Python>,地址为:http://interactivepython.org/runestone/static/pythonds/index.html是英文的,写的不错,里面代码的实现也很详细,很多…
自从工作后就没什么时间更新博客了,最近抽空学了点Python,觉得Python真的是很强大呀.想来在大学中没有学好数据结构和算法,自己的意志力一直不够坚定,这次想好好看一本书,认真把基本的数据结构和算法补一补. Python讲数据结构和算法的书,我想说的是真的太少了!!广泛搜索,中文的图书基本上没有,倒是找到两本外文的: Problem Solving with Algorithms and Data Structures (用Python讲解数据结构与算法) Python Algorithms…
