types.symbolic.SymbolicMatrix

types.symbolic.SymbolicMatrix

Matrix of symbolic expressions.

Used for vector-valued functions like state equations.

Shape: Can be any (m, n), commonly (n, 1) for column vectors

Examples

>>> import sympy as sp
>>> x1, x2 = sp.symbols('x1 x2')
>>> u = sp.symbols('u')
>>> 
>>> # Dynamics: dx/dt = f(x, u)
>>> f: SymbolicMatrix = sp.Matrix([
...     x2,
...     -x1 + u
... ])
>>> 
>>> # Jacobian
>>> A = f.jacobian([x1, x2])  # 2x2 matrix
>>> print(A)
>>> # Matrix([[0, 1], [-1, 0]])
>>> 
>>> # Access elements
>>> f[0]  # x2
>>> f[1]  # -x1 + u