Give a number for Variable

[quest]

I defined symbols via Sympy and I created an array. Then when I want to give a value to the variable, the variable still stay as variable.

a, b, c, d = sympy.symbols('a b c d')
error_mat=np.array([[a+d,b-c*1j],[b+c*1j,a-d]])
error_mat.shape

Then, after I found the correct values for my variables, I simply say that:

a=0.9685
b=0.0315
print(error_mat)
#error_mat.subs(a, 0.9685)
#error_mat.subs(b, 0.0315)

But my matrix is still:

[[a + d b - 1.0*I*c]
 [b + 1.0*I*c a - d]]

How can I update the variables?

[Larz60+]

After line 2 in 2nd code set you need to re-run
code error_mat=np.array([[a+d,b-c*1j],[b+c*1j,a-d]])

[ibreeden]

Or else have a look at eval().