核对记录(日期和数字值):给定两个具有多个功能的数据集,如何获得最可能的匹配?

时间:2019-02-24 06:06:02

标签: python machine-learning match

说我有两个数据集basepayment

base是:

[ id, timestamp, value]

payment是:

 [ payment_id, timestamp, value, gateway ]

我想使basepayment对帐。理想的结果是:

[id, timestamp, value, payment_id, gateway, probability]

基本上,它应该告诉我给定基本条目最可能的payment_id是什么。匹配应同时考虑日期时间和值。如果只给出最高的概率,我会感到满意,但也不会打扰我提出第二/第三建议。

到目前为止,我已经阅读了一些有关模糊匹配和相似性学习,余弦相似性和内容的内容,但是似乎无法将它们应用于我的问题。 我想到了手动这样的操作:

for each_entry in base:
    value_difference = base['value'] - payment['value']
    time_difference = base['timestamp'] - payment['timestamp']

    if value_difference <= 0.1 and time_difference <= 0.1:
        #if the difference is small, then tell me the payment_id.  

问题是,这看起来像是一种真正的“转储”方法,如果有多个payment_entry符合标准,则可能会发生冲突,并且我将不得不手动微调参数以获得良好的结果

我希望找到一种更智能,更自动的方式来协调这两个数据集。

有人对如何解决问题有任何建议吗?


编辑:我当前的状态:

import pandas as pd
import time
from itertools import islice
from pandas import ExcelWriter
import datetime
from random import uniform

orders = pd.read_excel("Orders.xlsx")
pmts = pd.read_excel("Payments.xlsx")

pmts['date'] = pd.to_datetime(pmts.date)
orders['data'] = pd.to_datetime(orders.data)

payment_list = []
for index, row in pmts.iterrows():
    new_entry = {}
    ts = row['date']
    new_entry['id'] = row['id']
    new_entry['date'] = ts.to_pydatetime()
    new_entry['value'] = row['value']
    new_entry['types'] = row['pmt']
    new_entry['results'] = []    
    payment_list.append(new_entry)

order_list = []
for index, row in orders.iterrows():
    new_entry = {}
    ts = row['data']
    new_entry['id'] = row['Id1']
    new_entry['date'] = ts.to_pydatetime()
    new_entry['value'] = row['valor']
    new_entry['types'] = row['nome']
    new_entry['results'] = []       
    order_list.append(new_entry)

for each_entry in order_list:
    for each_payment in payment_list:
        delta_value = (each_entry['value'] - each_payment['value'])
        try:
            delta_time = abs(each_entry['date'] - each_payment['date'])
        except:
            TypeError
            pass
        results = []
        delta_ref = datetime.timedelta(minutes=60)

        if delta_value == 0 and delta_time < delta_ref:
            result_type = each_payment['types']
            result_id = each_payment['id']
            results.append(result_type)
            results.append(delta_time)
            results.append(result_id)
            each_entry['results'].append(results)

            result_id = each_entry['id']
            each_payment['results'].append(result_id)



orders2 = pd.DataFrame(order_list)
writer = ExcelWriter('OrdersList.xlsx')
orders2.to_excel(writer)
writer.save()

pmts2 = pd.DataFrame(payment_list)
writer = ExcelWriter('PaymentList.xlsx')
pmts2.to_excel(writer)
writer.save()

好,现在我得到了一些东西。它向我返回所有具有相同值和小于x的时间增量(在这种情况下为60分钟)的条目。最好只给我最有可能的结果,也不会给出匹配正确的可能性(相同的数量,较短的时间范围)。将继续尝试。

1 个答案:

答案 0 :(得分:2)

最简单的方法可能是选择差异最小的基本/付款对。例如:

base_data = [...]  # all base data
payment_data = [...]  # all payment data

def prop_diff(a,b,props):
  # this iterates through all specified properties and
  # sums the result of the differences
  return sum([a[prop]-b[prop] for prop in props])


def join_data(base, payment):
  # you need to implement your merging strategy here
  return joined_base_and_payment


results = []  # where we will store our merged results
working_payment = payment_data.copy()
for base in base_data:
  # check the difference between the lists
  diffs = []
  for payment in working_payment:
    diffs.append(prop_diff(base, payment, ['value', 'timestamp']))

  # find the index of the payment with the minimum difference
  min_idx = 0
  for i, d in enumerate(diffs):
    if d < diffs[min_idx]:
      min_idx = i

  # append the result of the joined lists
  results.append(join_data(base, working_payment[min_idx]))
  del working_payment[min_idx]  # remove the selected payment

print(results)

基本思想是找到列表之间的总差异,并选择差异最小的对。在这种情况下,我复制了payment_data,因此我们不会破坏它,并且在将其与基数匹配并附加了结果之后,实际上删除了付款条目。