无法将字符串转换为浮点数 - Pandas 读取列
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Could not convert string to float - Pandas Read Column
提问by Sitz Blogz
I am trying to plot a scatter plot for the given input using Pandas. I am getting the following error.
我正在尝试使用 Pandas 为给定的输入绘制散点图。我收到以下错误。
Input:
输入：
tweetcricscore 34 #afgvssco 51
tweetcricscore 23 #afgvszim 46
tweetcricscore 24 #banvsire 12
tweetcricscore 456 #banvsned 46
tweetcricscore 653 #canvsnk 1
tweetcricscore 789 #cricket 178
tweetcricscore 625 #engvswi 46
tweetcricscore 86 #hkvssco 23
tweetcricscore 3 #indvsban 1
tweetcricscore 87 #sausvsvic 8
tweetcricscore 98 #wt20 56
Code:
代码：
import numpy as np
import matplotlib.pyplot as plt
from pylab import*
import math
from matplotlib.ticker import LogLocator
import pandas as pd
df = pd.read_csv('input.csv', header = None)
df.columns = ['col1','col2','col3','col4']
plt.scatter(x='col2', y='col4', s=120, c='b', label='Highly Active')
plt.legend(loc='upper right')
plt.xlabel('Freq (x)')
plt.ylabel('Freq(y)')
#plt.gca().set_xscale("log")
#plt.gca().set_yscale("log")
plt.show()
From 4 columns I am trying to plot col[1] and col[3] data points as pair in scatter plot.
我试图从 4 列中将 col[1] 和 col[3] 数据点绘制为散点图中的一对。
Error
错误
Traceback (most recent call last):
File "00_scatter_plot.py", line 14, in <module>
plt.scatter(x='col2', y='col3', s=120, c='b', label='Highly Active')
File "/usr/lib/pymodules/python2.7/matplotlib/pyplot.py", line 3087, in scatter
linewidths=linewidths, verts=verts, **kwargs)
File "/usr/lib/pymodules/python2.7/matplotlib/axes.py", line 6337, in scatter
self.add_collection(collection)
File "/usr/lib/pymodules/python2.7/matplotlib/axes.py", line 1481, in add_collection
self.update_datalim(collection.get_datalim(self.transData))
File "/usr/lib/pymodules/python2.7/matplotlib/collections.py", line 185, in get_datalim
offsets = np.asanyarray(offsets, np.float_)
File "/usr/local/lib/python2.7/dist-packages/numpy/core/numeric.py", line 514, in asanyarray
return array(a, dtype, copy=False, order=order, subok=True)
ValueError: could not convert string to float: col2
采纳答案by dot.Py
This is your error message:
这是您的错误消息：
File "00_scatter_plot.py", line 14, in <module>
plt.scatter(x='col2', y='col3', s=120, c='b', label='Highly Active')
ValueError: could not convert string to float: col2
As you can see you're trying to convert a string "col2" to float.
如您所见，您正在尝试将字符串“col2”转换为浮点数。
By taking a look at your code, it seems that you wanna something like this:
通过查看您的代码，您似乎想要这样的东西：
plt.scatter(x=df['col2'], y=df['col4'], s=120, c='b', label='Highly Active')
instead of:
代替：
plt.scatter(x='col2', y='col4', s=120, c='b', label='Highly Active')
回答by MaxU
try to change:
尝试改变：
plt.scatter(x='col2', y='col4', s=120, c='b', label='Highly Active')
to:
到：
df.plot.scatter(x='col2', y='col4', s=120, c='b', label='Highly Active')
it worked for me:
它对我有用：
