# Create an array of intervals to calculate total costs
intervals = np.linspace(30, 365, 50)
total_costs = []
maintenance_costs = []
failure_costs = []

interval.STATUS = 0
for i in intervals:
    interval.value = i
    m.solve(disp=False)  # Solve for each interval value
    total_costs.append(total_cost.value[0])
    maintenance_costs.append(maintenance_cost.value[0])
    failure_costs.append(failure_cost.value[0])

# Plot total cost vs. interval
plt.figure(figsize=(7, 4))
plt.plot(intervals, total_costs, label='Total Cost')
plt.plot(intervals, maintenance_costs, label='Maintenance Cost')
plt.plot(intervals, failure_costs, label='Failure Cost')
plt.axvline(opt, color='red', linestyle='--',
            label=f'Optimized Interval: {opt:.2f} days')
plt.xlabel('Maintenance Interval (days)')
plt.ylabel('Total Cost ($)')
plt.legend(); plt.grid(True)
plt.savefig('total_cost_vs_interval.png', dpi=300)
plt.show()