## R语言中赋值操作符“=”与“<-”的区别

x <- y <- 5
x = y  = 5
x <- y = 5
#Error in x <- y = 5 : could not find function "<-<-"


## CRAN Task View: Chemometrics and Computational Physics

Maintainer:
Katharine Mullen

Contact:
katharine.mullen at stat.ucla.edu

Version:
2016-02-18

Chemometrics and computational physics are concerned with the analysis of data arising in chemistry and physics experiments, as well as the[……]

$h(x) = {h_\theta }(x) = {\theta _0} + {\theta _1}{x_1} + {\theta _2}{x_2} + …$或者向量形式为：\[[……]

## 1.引言

• 写完前两篇逻辑回归的介绍和各个角度理解之后，小伙伴们纷纷表示『好像很高级的样纸，but**_然并卵_**啊！你们倒是拿点实际数据来给我们看看，这玩意儿 有！什！么！用！啊！』
• talk is cheap, show me the code！
• no example say a jb！

OK，OK，这就来了咯，同学们别着急，我们先找个简单的实际例子，来看看，所谓的数据挖掘或者机器学习实际应用到底是怎么样一个过程。[……]

1、T检验和F检验的由来

## 使用R制作六边形(苯环)地图

Hexamaps are gaining in popularity. Most notably has been the versions, where the map of the USA has been made into a hexamap.

The idea is that one unit is one hexagon. So in case of the US, each state is one hexagon. In the case of Europe, each country is a hexagon.

This means that all units (sta[……]

## Python解偏微分方程

In the world of scientific computing, the two major languages are of course C and FORTRAN. Both of these are compiled, low level and high performance languages. Generally, one rarely considers an executed language for scientific grunt-work since interpreted languages tend to be drastically slower. I[……]