Question

我有以下数据框

X
  X1 X2 X3 X4 X5
1  1  0  1  0  1
2  1  1  0  0  0
3  1  1  0  0  1
4  0  0  1  1  0
5  1  0  0  0  0
6  1  2  3  0  0

一个载体

pattern
[1] 0 1 0

X ==模式是什么意思？我无法解释以下输出。

> X == pattern
     X1    X2    X3    X4    X5
1 FALSE  TRUE FALSE  TRUE FALSE
2  TRUE  TRUE FALSE FALSE FALSE
3 FALSE FALSE  TRUE  TRUE FALSE
4  TRUE  TRUE FALSE FALSE  TRUE
5  TRUE FALSE FALSE FALSE FALSE
6 FALSE FALSE FALSE  TRUE  TRUE

Answer 1

看起来正在发生的事情，是将X中的值与从pattern [1]开始的逐行模式进行比较。

X[1,] is compared to pattern[1],
Then X[2,] is compared to pattern[2]
Then X[3,] is compared to pattern[3]
Then X[4,] is compared to pattern[1]
Then X[5,] is compared to pattern[2]... and so on.

如下所示创建比较

   X1    X2    X3    X4    X5
1  1==0  0==0  1==0  0==0  1==0   #pattern = 0
2  1==1  1==1  0==1  0==1  0==1   #pattern = 1
3  1==0  1==0  0==0  0==0  1==0   #pattern = 0
4  0==0  0==0  1==0  1==0  0==0   #pattern = 0
5  1==1  0==1  0==1  0==1  0==1   #pattern = 1
6  1==0  2==0  3==0  0==0  0==0   #pattern = 0

Answer 2

模式0,1,0小于数据框的大小，因此它将被复制足够的次数，以便可以进行所有必要的比较，使其与制作矩阵相同

(M = matrix(c(0,1,0), nrow=6, ncol=5))
     [,1] [,2] [,3] [,4] [,5]
[1,]    0    0    0    0    0
[2,]    1    1    1    1    1
[3,]    0    0    0    0    0
[4,]    0    0    0    0    0
[5,]    1    1    1    1    1
[6,]    0    0    0    0    0

并说X == M

Answer 3

您可以将操作理解为：它将matrix / data.frame转换为vector（按列）并使用它与模式进行比较。然后将结果（按列）返回matrix / data.frame。

# X == pattern is equal to:
matrix(c(as.matrix(X)) == pattern, ncol=ncol(X))

#       [,1]  [,2]  [,3]  [,4]  [,5]
# [1,] FALSE  TRUE FALSE  TRUE FALSE
# [2,]  TRUE  TRUE FALSE FALSE FALSE
# [3,] FALSE FALSE  TRUE  TRUE FALSE
# [4,]  TRUE  TRUE FALSE FALSE  TRUE
# [5,]  TRUE FALSE FALSE FALSE FALSE
# [6,] FALSE FALSE FALSE  TRUE  TRUE

你可以做一些实验，如：

Y <- X[-6, ]
Y

#   X1 X2 X3 X4 X5
# 1  1  0  1  0  1
# 2  1  1  0  0  0
# 3  1  1  0  0  1
# 4  0  0  1  1  0
# 5  1  0  0  0  0

Y == pattern

#      X1    X2   X3    X4    X5
# 1 FALSE  TRUE TRUE  TRUE FALSE
# 2  TRUE FALSE TRUE FALSE  TRUE
# 3 FALSE  TRUE TRUE  TRUE  TRUE
# 4  TRUE  TRUE TRUE FALSE  TRUE
# 5  TRUE  TRUE TRUE FALSE  TRUE    

matrix(c(as.matrix(Y)) == pattern, ncol=ncol(Y))

#       [,1]  [,2] [,3]  [,4]  [,5]
# [1,] FALSE  TRUE TRUE  TRUE FALSE
# [2,]  TRUE FALSE TRUE FALSE  TRUE
# [3,] FALSE  TRUE TRUE  TRUE  TRUE
# [4,]  TRUE  TRUE TRUE FALSE  TRUE
# [5,]  TRUE  TRUE TRUE FALSE  TRUE

数据

X <- structure(list(X1 = c(1L, 1L, 1L, 0L, 1L, 1L), X2 = c(0L, 1L, 
1L, 0L, 0L, 2L), X3 = c(1L, 0L, 0L, 1L, 0L, 3L), X4 = c(0L, 0L, 
0L, 1L, 0L, 0L), X5 = c(1L, 0L, 1L, 0L, 0L, 0L)), .Names = c("X1", 
"X2", "X3", "X4", "X5"), class = "data.frame", row.names = c("1", 
"2", "3", "4", "5", "6"))

数据框等于模式意味着什么

3 个答案:

数据