R语言线性代数方程 – solve()函数

R语言中的 solve() 函数是用来解决线性代数方程的。这里的方程是a*x=b，其中b是一个向量或矩阵，x是一个变量，其值将被计算。

语法： solve(a, b)

参数：

a：方程的系数

b：方程的向量或矩阵

例1 :

# R program to illustrate
# solve function
  
# Calling solve() function to
# calculate value of x in
# ax = b, where a and b is 
# taken as the arguments
solve(5, 10)
solve(2, 6)
solve(3, 12)

输出

[1] 2
[1] 3
[1] 4

例2 :

# R program to illustrate
# solve function
  
# Create 3 different vectors 
# using combine method. 
a1 <- c(3, 2, 5) 
a2 <- c(2, 3, 2) 
a3 <- c(5, 2, 4) 
    
# bind the three vectors into a matrix  
# using rbind() which is basically 
# row-wise binding
A <- rbind(a1, a2, a3) 
    
# print the original matrix 
print(A) 
    
# Use the solve() function  
# to calculate the inverse
T1 <- solve(A) 
    
# print the inverse of the matrix
print(T1)

输出

   [, 1] [, 2] [, 3]
a1    3    2    5
a2    2    3    2
a3    5    2    4
              a1          a2         a3
[1, ] -0.29629630 -0.07407407  0.4074074
[2, ] -0.07407407  0.48148148 -0.1481481
[3, ]  0.40740741 -0.14814815 -0.1851852