How to convert or extract symbolic matrix expressions to string?

For symbolic matrix expression of symbolic matrix 'D', I want to convert or extract any variable type with char and str.

How to convert or extract symbolic matrix expressions to string?

Thank you.

N = 100;
A = symmatrix('A',[N, N]);
B = symmatrix('B',[N, N]);
C = symmatrix('C',[N, N]);

D = A*B*C;

[Dyuman Joshi]

It might be difficult with symmatrix or maybe not even possible.

This might be a workaround -

N = 3;
syms A B C [N N]
D = A*B*C

D = 

E = string(D)

E = 3×3 string array
    "C1_1*(A1_1*B1_1 + A1_2*B2_1 + A1_3*B3_1) + C2_1*(A1_1*B1_2 …"    "C1_2*(A1_1*B1_1 + A1_2*B2_1 + A1_3*B3_1) + C2_2*(A1_1*B1_2 …"    "C1_3*(A1_1*B1_1 + A1_2*B2_1 + A1_3*B3_1) + C2_3*(A1_1*B1_2 …"
    "C1_1*(A2_1*B1_1 + A2_2*B2_1 + A2_3*B3_1) + C2_1*(A2_1*B1_2 …"    "C1_2*(A2_1*B1_1 + A2_2*B2_1 + A2_3*B3_1) + C2_2*(A2_1*B1_2 …"    "C1_3*(A2_1*B1_1 + A2_2*B2_1 + A2_3*B3_1) + C2_3*(A2_1*B1_2 …"
    "C1_1*(A3_1*B1_1 + A3_2*B2_1 + A3_3*B3_1) + C2_1*(A3_1*B1_2 …"    "C1_2*(A3_1*B1_1 + A3_2*B2_1 + A3_3*B3_1) + C2_2*(A3_1*B1_2 …"    "C1_3*(A3_1*B1_1 + A3_2*B2_1 + A3_3*B3_1) + C2_3*(A3_1*B1_2 …"

E(1)

ans = "C1_1*(A1_1*B1_1 + A1_2*B2_1 + A1_3*B3_1) + C2_1*(A1_1*B1_2 + A1_2*B2_2 + A1_3*B3_2) + C3_1*(A1_1*B1_3 + A1_2*B2_3 + A1_3*B3_3)"

[Lee Jong Hyun]

Thanks!

Answer 1

[Anjaneyulu Bairi]

I understand that you are trying to convert symbolic matrix expression into string.

You can use “string” function to convert it.

To avoid error while converting to string, please use “syms” like below instead of “symmatrix” to create symbolic matrix.

N=100
S = sym('S', [N N])
S_str=string(S)

“S_str” is the string form of “S” symbolic expression.

Hope it helps!