How can I find the elements of the X matrix in Matlab?

Question

当我在Matlab中得到X（transpost）与X.（非埃尔米特矩阵）的乘积时，如何找到X矩阵的元素？

X'*X = [ 10+2*i  2+3*i  90+5*i ; 2+36*i 56-3*i 52+37*i  ; 8+13*i   20+13*i  20-9*i ]

Answer 1

Option #1 - fsolve

Use fsolve - see example 2 .

Option #2 - solve

1. You have n^2 variables {a_ij} [i,j = 0,...,n] each variable corresponds to a matrix entery.
2. for each one of the variable in A'*A define an eqution and solve the n^2 equations. eg A11^2 +A12*A21 +A13*A31 = 10+2*i . using symbolic variable and solve function

---

>> s = solve(a^2+3 ==5, u+v+a ==32, a*u==1)

s = 

    a: [2x1 sym]
    u: [2x1 sym]
    v: [2x1 sym]

>> s.a

ans =

  2^(1/2)
 -2^(1/2)

>> s.v

ans =

 32 - (3*2^(1/2))/2
 (3*2^(1/2))/2 + 32

>> s.u

ans =

  2^(1/2)/2
 -2^(1/2)/2