python - '％s不在索引中'％objarr [mask]

我有以下代码：

##Overall reported expertise men vs women

import sys, re
import numpy as np
import smtplib
import matplotlib.pyplot as plt
from random import randint
import csv
import pylab as pl
import math
import pandas as pd
from pandas.tools.plotting import scatter_matrix
import argparse

parser = argparse.ArgumentParser()
parser.add_argument('-inVar', '--x', help = 'independent variable')

if len(sys.argv) == 1:
    parser.print_help()
    sys.exit(1)

args = parser.parse_args()

##Manipulating data so it can be graphed more easily
df1 = pd.read_csv('atc17-pcinfo.csv')
df1['Gender'] = df1['Gender'].replace(['M'], int(1))
df1['Gender'] = df1['Gender'].replace(['F'], int(2))
df1['Gender'] = df1['Gender'].convert_objects(convert_numeric = True)

x = df1['Gender']
y = df1['topic: Big data infrastructure']
print list(df1)

ax = df1.plot.scatter(x = x, y = y)
labels = [item.get_text() for item in ax.get_xticklabels()]
labels[1] = 'M'
labels[6] = 'F'
ax.set_xticklabels(labels)
#ax.set_title(y + ' vs. ' + x, fontsize=20)
plt.xlabel(x, fontsize=16)
plt.ylabel(y, fontsize=16)
plt.show()

我正在尝试使用df1中的数据创建散点图。处理完数据后，我得到：

 Gender    topic: Big data infrastructure
    0     2     NaN
    1     1     -1
    2     1     -1
    3     1     -1
    4     2     1
    5     1     NaN
    6     1     NaN
    7     1     NaN
    8     1     -2
    9     1     1
    10    2     1
    11    1     NaN
    12    1     1
    13    1     -1
    14    1     1
    15    1     NaN
    16    1     NaN
    17    1     NaN
    18    1     -1
    19    1     -2
    20    2     1
    21    1     NaN
    22    1     NaN
    23    2     2
    24    1     -2
    25    2     2
    26    1     NaN
    27    1     2
    28    1     1
    29    1     NaN
    30    1     2
    31    1     NaN
    32    1     NaN
    33    2     2
    34    1     2

但是我得到这个错误：

     KeyError('%s not in index' % objarr[mask])
KeyError: '[ nan  -1.  -1.  -1.   1.  nan  nan  nan  -2.   1.   1.  nan   1.  -1.   1.\n  nan  nan  nan  -1.  -2.   1.  nan  nan   2.  -2.   2.  nan   2.   1.  nan\n   2.  nan  nan   2.   2.] not in index'

有人可以帮我找出原因吗？我看了一些资料，但没有看到我的例子与他们的关系如何。

最佳答案

我认为您有两个问题：

第一个是您滥用了x方法的y和scatter参数。应该为它们传递所需列的列名，而不是实际值！因此，应该这样使用：

ax = df1.plot.scatter(x = "Gender", y = "topic: Big data infrastructure")

第二个问题是您没有像使用“性别”那样将“大数据”列转换为数值。

这应该做的工作：

df1['topic: Big data infrastructure'] = df1['topic: Big data infrastructure'].convert_objects(convert_numeric = True)

由于在DataFrame操作期间会经常使用列名，因此建议您使用更短，更容易的名称...

下面有一个工作示例：

# Read your copied df, saved as test.csv
df1 = pd.read_csv("test.csv",sep=",")

#rename df for easier work
df1.columns = ["Gender","Big_Data"]

# convert strings into floats/integers
df1 = df1.convert_objects(convert_numeric=True)

#Create figure by selecting desired columns as input x and y
ax = df1.plot.scatter(x = "Gender", y ="Big_Data")
fig = ax.get_figure()
fig.savefig('its_working.png')

关于python - '％s不在索引中'％objarr [mask]，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/44549755/