supplyChainModel.py

from scipy.optimize import minimize, LinearConstraint, basinhopping
from math import floor
import numpy as np

#Setting up the pricing amounts for each supplier
supplierPrice             = [10.5,11,10]
supplierDiscountAmount    = [0.1,0.35,0.05]
supplierDiscountThreshold = [100,260,300]
n_suppliers               = len(supplierPrice)
#Our minimum order amount
requiredOrder             = 500

#The below function produces a total cost given an order amount for each supplier
#It expects an list input with an order amount for each supplier, eg: [100,100,100]
def func(orders,supplierPrice=supplierPrice,supplierDiscountAmount=supplierDiscountAmount,supplierDiscountThreshold=supplierDiscountThreshold):
  totalCost = []
  for i,j in enumerate(orders):
      itemsAtDiscount = floor(j/supplierDiscountThreshold[i])*supplierDiscountThreshold[i]
      discountCost    = itemsAtDiscount*supplierPrice[i]*(1-supplierDiscountAmount[i])
      nonDiscountCost = (j-itemsAtDiscount)*supplierPrice[i]
      totalCost.append(discountCost+nonDiscountCost)
  return sum(totalCost)