类型错误：不可散列类型：'numpy.ndarray' 和 plt.scatter()

我遇到了 plt.scatter() 函数的问题。错误消息说'类型错误：不可散列类型：'numpy.ndarray''我希望此代码创建 x 和 y 数据帧的散点图。当我在代码中输入一个样本单元时，这两个数据帧的大小相同 (88,2)。

import statistics  
import pandas as pd  
import numpy as np  
import matplotlib.pyplot as plt  
import os


df=pd.read_csv('example.csv') 



unit=(input("Enter unit here:"))  
ind1 = df['Unit'] == unit   
unitrows=ind1[ind1].index 


df=df.iloc[unitrows,:]

df=df['Date'].groupby([df.Material]).apply(list).reset_index()  

def ADIFinal(df):  
    docdtmeans=[] 
    for index, row in df.iterrows():
        x=np.diff((sorted(row['Date']))) 
        x=x[x!=0] 
        if x.any(): 
            x=abs(statistics.mean(x)) 
        else: 
            x=None 
        docdtmeans.append(x) 
    d={'Material':df['Material'], 'ADI':docdtmeans} 
    dfmeans=pd.DataFrame(data=d) 
    return dfmeans 

x=ADIFinal(df)
print(x) 

df=pd.read_csv('example.csv') 
df=df.iloc[unitrows,:] 
df=df['Quantity'].groupby([df.Material]).apply(list).reset_index()



def CV2Final(df):  
      cv2=[] 
      for index, row in df.iterrows(): 
        z=row['Quantity'] 
        if len(z)>1: 
            z=((((statistics.stdev(z)/statistics.mean(z)))**2))
        else:
            z=None 
        cv2.append(z) 
      d={'Material':df['Material'], 'cv2':cv2} 
      dfcv2=pd.DataFrame(data=d) 
      return dfcv2
y=CV2Final(df)   
print(y) 

fig, ax = plt.subplots(figsize=(10,10))
plt.scatter(x,y, color='black') #this is where I am having an issue.   
plt.xlim([0,10])   
plt.ylim([0,10])   
plt.title(unit)

以下是 csv 文件中的信息示例。（数字是第一列，材料是第二列，数量是第三列......）

     Material: Quantity: Unit: Date:
0    B         1         A     43455
1    B         1         A     43455
2    C         1         A     43455
3    C         1         A     43456
4    D         1         A     43455
5    D         1         A     43455
6    B         1         A     43455 
7    B         2         A     43455
8    B         8         A     43459
9    B         5         A     43467
10   B         3         A     43452
11   D         7         A     43451