如何在 while 循环中获取嵌套列表总值的总和？

Question

我正在尝试从限制为 500 个值的 binance api（python-binance）获取买卖订单。（500 个询问，500 个购买）。 我已经可以通过创建 500 个带有索引号的变量来实现这一点，但在我看来，必须有比编写 500 行代码更好的方法。 这是我试图实现它的代码。

#!/usr/bin/python
# -*- coding: utf-8 -*-
from binance.client import Client

user_key = ''
secret_key = ''
binance_client = Client(user_key, secret_key)

while True:
    alis = binance_client.futures_order_book(symbol='XRPUSDT')

    binance_buy = alis['bids'][0]
    binance_buy1 = alis['bids'][1]
    binance_buy2 = alis['bids'][2]
    binance_buy3 = alis['bids'][3]
    binance_buy4 = alis['bids'][4]
    binance_buy5 = alis['bids'][5]
    binance_buy6 = alis['bids'][6]
    binance_buy7 = alis['bids'][7]
    binance_buy8 = alis['bids'][8]
    binance_buy9 = alis['bids'][9]
    binance_buy10 = alis['bids'][10]
    binance_buy11 = alis['bids'][11]
    binance_buy12 = alis['bids'][12]
    binance_buy13 = alis['bids'][13]
    binance_buy14 = alis['bids'][14]
    binance_buy15 = alis['bids'][15]
    binance_buy16 = alis['bids'][16]
    binance_buy17 = alis['bids'][17]
    binance_buy18 = alis['bids'][18]
    binance_buy19 = alis['bids'][19]
    binance_buy20 = alis['bids'][20]
    binance_sell = alis['asks'][0]
    binance_sell1 = alis['asks'][1]
    binance_sell2 = alis['asks'][2]
    binance_sell3 = alis['asks'][3]
    binance_sell4 = alis['asks'][4]
    binance_sell5 = alis['asks'][5]
    binance_sell6 = alis['asks'][6]
    binance_sell7 = alis['asks'][7]
    binance_sell8 = alis['asks'][8]
    binance_sell9 = alis['asks'][9]
    binance_sell10 = alis['asks'][10]
    binance_sell11 = alis['asks'][11]
    binance_sell12 = alis['asks'][12]
    binance_sell13 = alis['asks'][13]
    binance_sell14 = alis['asks'][14]
    binance_sell15 = alis['asks'][15]
    binance_sell16 = alis['asks'][16]
    binance_sell17 = alis['asks'][17]
    binance_sell18 = alis['asks'][18]
    binance_sell19 = alis['asks'][19]
    binance_sell20 = alis['asks'][20]

    binance_buy_demand = float(binance_buy[1]) + float(binance_buy1[1]) \
        + float(binance_buy2[1]) + float(binance_buy3[1]) \
        + float(binance_buy4[1]) + float(binance_buy5[1]) \
        + float(binance_buy6[1]) + float(binance_buy7[1]) \
        + float(binance_buy8[1]) + float(binance_buy9[1]) \
        + float(binance_buy10[1]) + float(binance_buy11[1]) \
        + float(binance_buy12[1]) + float(binance_buy13[1]) \
        + float(binance_buy14[1]) + float(binance_buy15[1]) \
        + float(binance_buy16[1]) + float(binance_buy17[1]) \
        + float(binance_buy18[1]) + float(binance_buy19[1]) \
        + float(binance_buy20[1])

    for i in range(0, 500):
        print (alis['asks'][i][0], alis['asks'][i][1])

    binance_sell_demand = float(binance_sell[1]) \
        + float(binance_sell1[1]) + float(binance_sell2[1]) \
        + float(binance_sell3[1]) + float(binance_sell4[1]) \
        + float(binance_sell5[1]) + float(binance_sell6[1]) \
        + float(binance_sell7[1]) + float(binance_sell8[1]) \
        + float(binance_sell9[1]) + float(binance_sell10[1]) \
        + float(binance_sell11[1]) + float(binance_sell12[1]) \
        + float(binance_sell13[1]) + float(binance_sell14[1]) \
        + float(binance_sell15[1]) + float(binance_sell16[1]) \
        + float(binance_sell17[1]) + float(binance_sell18[1]) \
        + float(binance_sell19[1]) + float(binance_sell20[1])

得到数据后有 500 次出价和 500 次询问

我尝试创建 for 循环，但只能打印此值无法在 for 循环中求和这是我尝试的代码：示例 output：

0.9315 18328.6
0.9316 18201.2
0.9317 23544.0
0.9318 260.4
0.9319 689.5
0.9320 20410.5
0.9321 47.7
0.9322 294.2
0.9323 446.6
0.9324 104.0
0.9325 3802.3
0.9326 100.1
0.9327 20122.9
0.9328 1410.0
0.9329 7745.1
0.9330 9094.4
0.9331 10389.9
0.9332 248.5
0.9333 71559.7
0.9334 18024.1
0.9335 7404.5
0.9336 1366.6
0.9337 21972.4
0.9338 1224.8
0.9339 49.9
0.9340 17590.5
0.9341 17967.1
0.9342 272.3
0.9343 704.4
0.9344 3581.7
0.9345 3896.8

第一项是价格，第二项是数量

我正在尝试制作一个 function 求和并除以 avg.price 并且还想知道总共有多少出价和要价。

Answer 1

将sum() function 与生成器一起使用，该生成器获取每个列表项的适当元素。

binance_buy_demand = sum(float(x[1]) for x in alis['bids'])
binance_sell_demand = sum(float(x[1]) for x in alis['asks'])

Answer 2

您可以像这样在 for 循环中求和：

total_ask_volume = 0
total_bid_volume = 0
for i  in range(0, 500):
    total_ask_volume += float(alis["asks"][i][1])
    total_bid_volume += float(alis["bids"][i][1])
print(total_ask_volume, total_bid_volume)

另一种选择是跳过i索引，并直接通过值 go：

total_ask_volume = 0
for ask in alis["asks"]:
    total_ask_volume += float(ask[1])

total_bid_volume = 0
for bid in alis["bids"]:
    total_bid_volume += float(bid[1])

print(total_ask_volume, total_bid_volume)

这有时会更清楚，特别是在您有多个索引（ i 、 j 、 k等）的情况下，这可能会让人感到困惑。

作为旁注， float通常以不直观的方式四舍五入； 在这种特定情况下，这可能无关紧要，但在大多数涉及金钱的情况下，您可能想改用Decimal （或乘以 100 并计算美分的整数）。