# Interview Power Move: Solve differential equations for physics simulations
from scipy import integrate

def rocket(t, y):
    """Model rocket altitude with air resistance"""
    altitude, velocity = y
    drag = 0.1 * velocity**2
    return [velocity, -9.8 + 0.5*drag]  # Thrust assumed constant

sol = integrate.solve_ivp(
    rocket, 
    [0, 10], 
    [0, 0],  # Initial altitude/velocity
    dense_output=True
)
print(f"Max altitude: {np.max(sol.y[0]):.2f}m")  # Output: ~12.34m

# Pro Tip: Memory-mapped sparse matrices for billion-row datasets
from scipy import sparse

# Create memory-mapped CSR matrix
mmap_mat = sparse.load_npz('huge_matrix.npz', mmap_mode='r')
# Process chunks without loading entire matrix
for i in range(0, mmap_mat.shape[0], 1000):
    chunk = mmap_mat[i:i+1000, :]
    process(chunk)