python - 从命令行从输入文件绘制数据

我得到了一个名为“ density_air.dat”的数据文件，我需要从每一列中提取数据并将它们放入自己的列表中（即tList将以“ -10”开头的列中包含值，而密度将包含值在以“ 1.341”开头的列中，然后需要绘制列表。我在用这些数据填充列表时遇到了麻烦...任何帮助吗？

from scitools.std import *
import sys
import pylab as pl

inFile = sys.argv[-1]

f = open(inFile, 'r')

for x in range(4):
    f.readline()

tList = []
density = []

for line in f:
    words = line.split()
    for x in words:
        tList.append(words[x])
        density.append(words[x])

f.close()

plot(tList, density)

数据文件为：

# Density of air at different temperatures, at 1 atm pressure
# Column 1: temperature in Celsius degrees
# Column 2: density in kg/m^3

-10     1.341
-5     1.316
 0     1.293
 5     1.269
10     1.247
15     1.225
20     1.204
25     1.184
30     1.164
# Source: Wikipedia (keyword Density)

最佳答案

有一个名为numpy的loadtxt函数，该函数将ascii文件加载到numpy数组中：

import numpy as np
import matplotlib.pylab as plt
import sys

inFile = sys.argv[-1]
temperature, density = np.loadtxt(inFile,unpack=True)
plt.plot(temperature, density,'ko')
plt.show()