在python中的列中拆分数据

Question

我正在尝试编写一个从外部文件读取一组值的代码，如下所示：

   4.87320984E-09               1       49.882684417026184            0.18691906898647714            0.22222662961584136
   1.88917193E-09               2       49.882684417026184            0.18691906898647714            0.22222662961584136
   1.30942168E-09               3       49.882684417026184            0.18691906898647714            0.22222662961584136
   7.26580629E-10               4       49.882684417026184            0.18691906898647714            0.22222662961584136
   5.39025047E-10               5       49.882684417026184            0.18691906898647714            0.22222662961584136
   2.04686401E-08               1       68.253977742324736            -5.0977927905402787E-002       0.32783928527485512
   3.08666603E-09               3       68.253977742324736            -5.0977927905402787E-002       0.32783928527485512
   2.88387625E-09               4       68.253977742324736            -5.0977927905402787E-002       0.32783928527485512
   1.15430343E-09               5       68.253977742324736            -5.0977927905402787E-002       0.32783928527485512

我想将每一列存储在一个列表中并用它们做一些数学运算。

import sys
inFile = sys.argv[1]
c1 = []
c2 = []
c3 = []
c4 = []
c5 = []
data = [c1,c2,c3,c4,c5]

with open(inFile,'r') as i:
   lines = i.read().split('\n')
for row in lines:
   #split in columns and do some maths
print data

Answer 1

with open("inFile",'r') as dataFile:
   for i in dataFile.readlines():
       print i.split()

输出：

['4.87320984E-09', '1', '49.882684417026184', '0.18691906898647714', '0.22222662961584136']
['1.88917193E-09', '2', '49.882684417026184', '0.18691906898647714', '0.22222662961584136']
['1.30942168E-09', '3', '49.882684417026184', '0.18691906898647714', '0.22222662961584136']
['7.26580629E-10', '4', '49.882684417026184', '0.18691906898647714', '0.22222662961584136']
['5.39025047E-10', '5', '49.882684417026184', '0.18691906898647714', '0.22222662961584136']
['2.04686401E-08', '1', '68.253977742324736', '-5.0977927905402787E-002', '0.32783928527485512']
['3.08666603E-09', '3', '68.253977742324736', '-5.0977927905402787E-002', '0.32783928527485512']
['2.88387625E-09', '4', '68.253977742324736', '-5.0977927905402787E-002', '0.32783928527485512']
['1.15430343E-09', '5', '68.253977742324736', '-5.0977927905402787E-002', '0.32783928527485512']

Answer 2

import pandas as pd

inFile = YOUR_CSV.csv
df = pd.read_csv(inFile)
print(df.head(3) #prints first 3 rows to check your data

Answer 3

我肯定会推荐这项任务的熊猫。像这样的东西应该可以工作

import pandas as pd
data = pd.read_csv(inFile, delimiter=r'\s+', header=None)

分隔符参数告诉它将一个或多个空格字符视为分隔符。对于您的示例中显示的数据，它应该工作。

Answer 4

很多人都在推荐 pandas，但由于这个数据只包含数字，你可能只想考虑 numpy.一个很好的教程在这里：https://www.dataquest.io/blog/numpy-tutorial-python/。

以下是如何导入数据的示例。从那里您可以使用完整的 numpy 库对数组进行数学运算或大量操作。有关更多信息，请参阅我发布的教程。

import numpy as np

file = 'path_to_your_file.csv'

data_array = np.genfromtxt(file, delimiter=',')

Answer 5

这是您要查找的代码：

import sys
inFile = sys.argv[1]
c1 = []
c2 = []
c3 = []
c4 = []
c5 = []
data = [c1,c2,c3,c4,c5]

with open(inFile,'r') as i:
   for row in line:
       v1, v2, v3, v4, v5 = row.strip().split()
       c1.append(float(v1))
       c2.append(float(v2))
       c3.append(float(v3))
       c4.append(float(v4))
       c5.append(float(v5))
print data

但我建议使用 Pandas read_csv 方法。