Simplify: Python VS Matlab

Background

The homework of Linear System Theory is challenging. Here is Problem 1:

Consider a linear system with a state transition matrix

Compute A(t).

Since the given system is linear time variant system, by using some properties of , we can easily compute . However, the expression is so complicate that i could not simplify it by hand. I call for some tools for help. The tools are Python and Matlab.

This post compare the difference of simplify function in Python and Matlab. ## Comparision ### Python sympy.simplify.simplify.simplify(expr, ratio=1.7, measure=, rational=False, inverse=False). Link https://docs.sympy.org/latest/modules/simplify/simplify.html

This function does not work well, it did not simplify the expression, giving th following outcome.

It's rediculous!

Matlab

S = simplify(expr) performs algebraic simplification of expr. If expr is a symbolic vector or matrix, this function simplifies each element of expr. Link https://www.mathworks.com/help/symbolic/simplify.html

This function works very well and much faster than Sympy.