R语言——assignment3

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有如下数据：

> A<-c('Y','Y','N','N','Y')
> B<-c('N','Y','Y','Y','N')
> C<-c('Y','Y','Y','Y','N')
> D<-c('Y','Y','y','y','Y')
> E<-c('N','n','n','Y','N')
> F<-c('Y','n','Y','Y','y')
> test<-rbind(A,B,C,D,E,F)
> test
  [,1] [,2] [,3] [,4] [,5]
A "Y"  "Y"  "N"  "N"  "Y" 
B "N"  "Y"  "Y"  "Y"  "N" 
C "Y"  "Y"  "Y"  "Y"  "N" 
D "Y"  "Y"  "y"  "y"  "Y" 
E "N"  "n"  "n"  "Y"  "N" 
F "Y"  "n"  "Y"  "Y"  "y" 

将Y和y变为数字1，将N和n变为数字0

> test[which(test=='Y')]=1
> test[which(test=='y')]=1
> test
  [,1] [,2] [,3] [,4] [,5]
A "1"  "1"  "N"  "N"  "1" 
B "N"  "1"  "1"  "1"  "N" 
C "1"  "1"  "1"  "1"  "N" 
D "1"  "1"  "1"  "1"  "1" 
E "N"  "n"  "n"  "1"  "N" 
F "1"  "n"  "1"  "1"  "1" 
> test[which(test=='N')]=0
> test[which(test=='n')]=0
> test
  [,1] [,2] [,3] [,4] [,5]
A "1"  "1"  "0"  "0"  "1" 
B "0"  "1"  "1"  "1"  "0" 
C "1"  "1"  "1"  "1"  "0" 
D "1"  "1"  "1"  "1"  "1" 
E "0"  "0"  "0"  "1"  "0" 
F "1"  "0"  "1"  "1"  "1" 

计算距离
R语言中计算距离的函数为dist()

如：dist(x, method = "euclidean", diag = FALSE, upper = FALSE, p = 2)
#x是样本矩阵或者数据框。
method表示计算哪一种距离：
euclidean                欧几里德距离，就是平方再开方。
maximum                  切比雪夫距离
manhattan                绝对值距离
canberra                 Lance 距离
minkowski                明科夫斯基距离，使用时要指定p值
binary                   定性变量距离.

> distdata<-dist(test,method = "binary")
> distdata
          A         B         C         D         E
B 0.8000000                                        
C 0.6000000 0.2500000                              
D 0.4000000 0.4000000 0.2000000                    
E 1.0000000 0.6666667 0.7500000 0.8000000          
F 0.6000000 0.6000000 0.4000000 0.2000000 0.7500000