Price Elasticity Calculator

def price_elasticity(q1, q2, p1, p2):
    """
    Calculate price elasticity of demand using midpoint method.
    q1, q2: quantity demanded before and after price change
    p1, p2: price before and after
    """
    avg_q = (q1 + q2) / 2
    avg_p = (p1 + p2) / 2
    pct_change_q = (q2 - q1) / avg_q * 100
    pct_change_p = (p2 - p1) / avg_p * 100
    ped = pct_change_q / pct_change_p if pct_change_p != 0 else float('inf')
    return ped

# Example: price rises from $10 to $12, quantity falls from 100 to 80
ped = price_elasticity(100, 80, 10, 12)
print(f"Price Elasticity of Demand: {ped:.4f}")
abs_ped = abs(ped)
if abs_ped > 1:
    print("Elastic demand (|PED| > 1) - price-sensitive")
elif abs_ped < 1:
    print("Inelastic demand (|PED| < 1) - price-insensitive")
else:
    print("Unit elastic (|PED| = 1)")