def test_bug(): x1 = Symbol('x1') x2 = Symbol('x2') y = x1 * x2 assert y.subs(x1, Float(3.0)) == Float(3.0) * x2
# Transfer function K, J, b, R, L = sym.symbols('K J b R L') G = K / (s * ((J * s + b) * (L * s + R) + K**2)) G = G.subs([(K, 0.0274), (J, 3.2284E-6), (b, 3.5077E-6), (R, 4), (L, 2.75E-6)]) # Calculate response Y = G * U # Inverse Laplace Transform u = inverse_laplace_transform(U, s, t) y = inverse_laplace_transform(Y, s, t) # generate data for plot tm = np.linspace(0, 8, 100) us = np.zeros(len(tm)) ys = np.zeros(len(tm)) # substitute numeric values for u and y for i in range(len(tm)): us[i] += u.subs(t, tm[i]) ys[i] += y.subs(t, tm[i]) # Plot the results plt.figure() plt.plot(tm, us, label='u(t)') plt.plot(tm, ys, label='y(t)') plt.legend() plt.xlabel('Time') plt.show()
def test_bug(): x1 = Symbol("x1") x2 = Symbol("x2") y = x1 * x2 assert y.subs(x1, Float(3.0)) == Float(3.0) * x2
def test_bug(): x1 = Symbol('x1') x2 = Symbol('x2') y = x1*x2 assert y.subs(x1, Float(3.0)) == Float(3.0)*x2