在Python中将文件输入行读入多个列表

2024-04-19 09:09:01 发布

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我试图将以下文件中的行读入3个列表，其中第二列（读取到2位小数）包含x值，第三列包含y值。当行号（第一列）从1开始时，我需要一个新的列表。你知道吗

1 0.05 0 2 0.1 0 3 0.15 0 4 0.2 0 5 0.25 0 6 0.3 0 7 0.35 0 8 0.4 1 9 0.45 1 10 0.5 2 11 0.55 3 12 0.6 4 13 0.65 5 14 0.7 6 15 0.75 7 16 0.8 8 17 0.85 8 18 0.9 9 19 0.95 10 20 1 11 1 0.047619 0 2 0.0952381 1 3 0.142857 1 4 0.190476 1 5 0.238095 1 6 0.285714 1 7 0.333333 1 8 0.380952 1 9 0.428571 1 10 0.47619 1 11 0.52381 2 12 0.571429 3 13 0.619048 4 14 0.666667 5 15 0.714286 5 16 0.761905 5 17 0.809524 6 18 0.857143 7 19 0.904762 8 20 0.952381 8 21 1 9 1 0.0526316 0 2 0.105263 0 3 0.157895 0 4 0.210526 0 5 0.263158 1 6 0.315789 1 7 0.368421 1 8 0.421053 1 9 0.473684 2 10 0.526316 3 11 0.578947 3 12 0.631579 3 13 0.684211 4 14 0.736842 5 15 0.789474 5 16 0.842105 6 17 0.894737 7 18 0.947368 8 19 1 9

我有以下代码。当我去绘制它们时，只绘制x1和y1。起初我认为这是我的绘图代码的问题，但后来当我分别绘制它们时，我发现列表x2、y2、x3、y3是空的，这使我相信列表没有正确读取值。你知道吗

import numpy as np import matplotlib.pyplot as plt with open('kmt_oa.txt') as f: lines1 = f.readlines()[0:20] x1 = [line.split()[1][:4] for line in lines1] y1 = [line.split()[2] for line in lines1] lines2 = f.readlines()[21:40] x2 = [line.split()[1][:4] for line in lines2] y2 = [line.split()[2] for line in lines2] lines3 = f.readlines()[41:60] x3 = [line.split()[1][:4] for line in lines3] y3 = [line.split()[2] for line in lines3] ax1 = plt.subplot() ax1.scatter(x1, y1, color = 'r', label = 'Table size of 20') ax1.scatter(x2, y2, color = 'g', label = 'Table size of 21') ax1.scatter(x3, y3, color = 'b', label = 'Table size of 19') ax1.set_xlabel('Load Factor') ax1.set_ylabel('Number of Collisions') ax1.set_title("Key Mod Tablesize & Open Addressing") ax1.set_ylabel('Number of Collisions') plt.legend(loc = 'upper left') plt.show()

Tags： ofin列表forline绘制pltsplit
3条回答
网友
1楼 · 编辑于 2024-04-19 09:09:01

您也可以使用纯Python而不使用任何模块：

outList = []
with open('data.txt', 'r') as inFile:
   # Create small lists of each individual record.
   content = [elem.split() for elem in inFile.read().split('\n')]
   # Find the indices of these elements whose first number is 1.
   indices = [i for i in range(len(content)) if content[i][0]=='1'] + [len(content)]
   # Remove the first element of each record.
   content = [elem[1:] for elem in content]
   # Create lists, based on the indices above.
   outList = [sum([],content[indices[i]:indices[i+1]]) for i in range(0,len(indices)-1,1)]

for elem in outList:
    for item in elem:
        print(item)
    print()

结果：

['0.05', '0']
['0.1', '0']
['0.15', '0']
['0.2', '0']
['0.25', '0']
['0.3', '0']
['0.35', '0']
['0.4', '1']
['0.45', '1']
['0.5', '2']
['0.55', '3']
['0.6', '4']
['0.65', '5']
['0.7', '6']
['0.75', '7']
['0.8', '8']
['0.85', '8']
['0.9', '9']
['0.95', '10']
['1', '11']

['0.047619', '0']
['0.0952381', '1']
['0.142857', '1']
['0.190476', '1']
['0.238095', '1']
['0.285714', '1']
['0.333333', '1']
['0.380952', '1']
['0.428571', '1']
['0.47619', '1']
['0.52381', '2']
['0.571429', '3']
['0.619048', '4']
['0.666667', '5']
['0.714286', '5']
['0.761905', '5']
['0.809524', '6']
['0.857143', '7']
['0.904762', '8']
['0.952381', '8']
['1', '9']

['0.0526316', '0']
['0.105263', '0']
['0.157895', '0']
['0.210526', '0']
['0.263158', '1']
['0.315789', '1']
['0.368421', '1']
['0.421053', '1']
['0.473684', '2']
['0.526316', '3']
['0.578947', '3']
['0.631579', '3']
['0.684211', '4']
['0.736842', '5']
['0.789474', '5']
['0.842105', '6']
['0.894737', '7']
['0.947368', '8']
['1', '9']
网友
2楼 · 编辑于 2024-04-19 09:09:01

使用以下代码，您将在lists对象中拥有一个列表列表。你知道吗

with open(path, 'r') as f:
  lists = []
  current = [[], []]
  card = 0
  for line in f.readlines():
    idx, x, y = line.split()
    if idx < card:
      card = idx
      lists.append(current)
      continue

    card = idx
    current[0].append(int(x * 100) / 100)
    current[1].append(y)
网友
3楼 · 编辑于 2024-04-19 09:09:01

可以使用csv.reader读取行并将其作为序列生成，使用enumerate函数生成行索引，然后将itertools.groupby与返回行索引和行号（第一个字段）之差的键函数一起使用，以便可以按连续的行号序列对列表进行分组（假定您的文件对象f已经打开）：

from itertools import groupby
import csv
[[[round(float(r[1]), 2), int(r[2])] for _, r in g] for _, g in groupby(enumerate(csv.reader(f, delimiter=' ')), key=lambda t: t[0] - int(t[1][0]))]

这将返回：

[[[0.05, 0],
  [0.1, 0],
  [0.15, 0],
  [0.2, 0],
  [0.25, 0],
  [0.3, 0],
  [0.35, 0],
  [0.4, 1],
  [0.45, 1],
  [0.5, 2],
  [0.55, 3],
  [0.6, 4],
  [0.65, 5],
  [0.7, 6],
  [0.75, 7],
  [0.8, 8],
  [0.85, 8],
  [0.9, 9],
  [0.95, 10],
  [1.0, 11]],
 [[0.05, 0],
  [0.1, 1],
  [0.14, 1],
  [0.19, 1],
  [0.24, 1],
  [0.29, 1],
  [0.33, 1],
  [0.38, 1],
  [0.43, 1],
  [0.48, 1],
  [0.52, 2],
  [0.57, 3],
  [0.62, 4],
  [0.67, 5],
  [0.71, 5],
  [0.76, 5],
  [0.81, 6],
  [0.86, 7],
  [0.9, 8],
  [0.95, 8],
  [1.0, 9]],
 [[0.05, 0],
  [0.11, 0],
  [0.16, 0],
  [0.21, 0],
  [0.26, 1],
  [0.32, 1],
  [0.37, 1],
  [0.42, 1],
  [0.47, 2],
  [0.53, 3],
  [0.58, 3],
  [0.63, 3],
  [0.68, 4],
  [0.74, 5],
  [0.79, 5],
  [0.84, 6],
  [0.89, 7],
  [0.95, 8],
  [1.0, 9]]]

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