Question

R中有Galois字段（GF）的包吗？我想用GF定义以下矩阵运算。

1 + 1 = 0
1 + 0 = 1
0 + 1 = 1
0 + 0 = 0

显然，R不理解1+1而没有指定它：

> k <- matrix(c(0,1,1,0,1,0,0,0,0,1), ncol=10);k
     [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,]    0    1    1    0    1    0    0    0    0     1
> p <- matrix(c(0,0,0,1,1,1,0,1,0,1), ncol=10);p
     [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,]    0    0    0    1    1    1    0    1    0     1
> c <- k+p;c
     [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,]    0    1    1    1    2    1    0    1    0     2

Answer 1

我对Galois字段一无所知，但从this question来看，加法和减法似乎等同于xor。使用这个事实进行计算可能更容易。

as.integer(xor(k,p))

或者，如果你想变得非常花哨，你可以重载运算符并定义你自己的类：

`+.GF`<-function (x, y) as.integer((x | y) & !(x & y))
class(k)<-'GF'
class(p)<-'GF'
k+p
[1] 0 1 1 1 0 1 0 1 0 0

Answer 2

您可以自己定义一个功能。看起来你只是做布尔算法。

myadd <- function(x, y){(x+y) %% 2}

实施例

> a <- matrix(c(0,0,1,1),2,2)
> b <- matrix(c(0,1,0,1),2,2)
> a
     [,1] [,2]
[1,]    0    1
[2,]    0    1
> b
     [,1] [,2]
[1,]    0    0
[2,]    1    1
> myadd(a,b)
     [,1] [,2]
[1,]    0    1
[2,]    1    0

伽罗瓦场（GF）与R.

2 个答案: