如何迭代此列表以创建矩阵？答案

【问题标题】：How do I iterate this list to create a matrix?如何迭代此列表以创建矩阵？
【发布时间】：2018-10-05 05:21:24
【问题描述】：

在线课程中，部分练习是创建矩阵。

我们得到了以下数据：

KobeBryant_FT = [696,667,623,483,439,483,381,525,18,196]
JoeJohnson_FT = [261,235,316,299,220,195,158,132,159,141]
LeBronJames_FT = [601,489,549,594,593,503,387,403,439,375]
CarmeloAnthony_FT = [573,459,464,371,508,507,295,425,459,189]
DwightHoward_FT = [356,390,529,504,483,546,281,355,349,143]
ChrisBosh_FT = [474,463,472,504,470,384,229,241,223,179]
ChrisPaul_FT = [394,292,332,455,161,337,260,286,295,289]
KevinDurant_FT = [209,209,391,452,756,594,431,679,703,146]
DerrickRose_FT = [146,146,146,197,259,476,194,0,27,152]
DwayneWade_FT = [629,432,354,590,534,494,235,308,189,284]

为了创建一个矩阵，代码如下：

FT = np.array([KobeBryant_FT, JoeJohnson_FT, LeBronJames_FT, 
               CarmeloAnthony_FT, DwightHoward_FT, ChrisBosh_FT, ChrisPaul_FT,
               KevinDurant_FT, DerrickRose_FT, DwayneWade_FT])

我想知道是否有一种方法可以使用“for”循环来模拟上述代码的输出，而无需手动输入 KobeBryant_FT、JoeJohnson_FT、LeBronJames_FT 等。

【问题讨论】：

你提到的解决方案很好。您不会在这里使用 for 循环，但如果您想尝试，请查看 np.append() 或 np.vstack() 并遍历列表：for x in [KobeBryant_FT, JoeJohnson_FT, LeBronJames_FT, CarmeloAnthony_FT, DwightHoward_FT, ChrisBosh_FT, ChrisPaul_FT, KevinDurant_FT, DerrickRose_FT, DwayneWade_FT]:

标签： python arrays for-loop

【解决方案1】：

这取决于您将如何接收这些数据。如果它在 *.txt 文件中，那么您可以阅读它line by line（如果您想在列表中同时指定名称）或一次阅读所有内容，然后使用 regular expression 查找正方形内的任何内容括号。

import re

file = open("data.txt","r").read()

lists_txt = re.finditer('[\[].*[\]]$', file, flags=re.MULTILINE)
#item in lists_txt = anything found inside [] brackets.

for item in lists_txt:
    txt = str(item.group(0))
    print(txt[1:-1])

程序输出：

696,667,623,483,439,483,381,525,18,196
261,235,316,299,220,195,158,132,159,141
601,489,549,594,593,503,387,403,439,375
573,459,464,371,508,507,295,425,459,189
356,390,529,504,483,546,281,355,349,143
474,463,472,504,470,384,229,241,223,179
394,292,332,455,161,337,260,286,295,289
209,209,391,452,756,594,431,679,703,146
146,146,146,197,259,476,194,0,27,152
629,432,354,590,534,494,235,308,189,284

你应该得到 [] 内的任何东西的字符串。现在通过using .split(",")，您可以将它们转换为列表。

希望对你有所帮助:)

【讨论】：

【解决方案2】：

试试这个，

import pandas as pd
df = pd.DataFrame(FT)

【讨论】：

【解决方案3】：

创建列表时，可以将它们放入字典中，以便更轻松地引用它们：

d = {"KB":[696,667,623,483,439,483,381,525,18,196], "JJ":[261,235,316,299,220,195,158,132,159,141]}
np.stack(d.values())
# Out[32]: 
# array([[261, 235, 316, 299, 220, 195, 158, 132, 159, 141],
#        [696, 667, 623, 483, 439, 483, 381, 525,  18, 196]])

如果您希望数组按特定顺序排列，您可以使用 Ordereddict：

from collections import OrderedDict
d = OrderedDict({"KB":[696,667,623,483,439,483,381,525,18,196], "JJ":[261,235,316,299,220,195,158,132,159,141]})
np.stack(d.values())

【讨论】：