In [1]:
import numpy as np
import pandas as pd
In [2]:
df = pd.DataFrame(data=[[1, 2, 3], [4, 5, 6]], columns=['a', 'b', 'c'])
print(df)
In [3]:
a_values = df.values
print(a_values)
In [4]:
print(np.shares_memory(a_values, df))
In [5]:
a_values[0, 0] = 100
print(a_values)
In [6]:
print(df)
In [7]:
df_if = pd.DataFrame(data=[[1, 0.1], [2, 0.2]], columns=['int', 'float'])
print(df_if)
In [8]:
print(df_if.dtypes)
In [9]:
a_values_if = df_if.values
print(a_values_if)
In [10]:
print(np.shares_memory(a_values_if, df_if))
In [11]:
a_values_if[0, 0] = 100
print(a_values_if)
In [12]:
print(df_if)
In [13]:
print(df[['a', 'c']].values)
In [14]:
print(np.shares_memory(df[['a', 'c']].values, df))
In [15]:
print(df.iloc[:, ::2].values)
In [16]:
print(np.shares_memory(df.iloc[:, ::2].values, df))
In [17]:
a_values_copy = df.values.copy()
print(a_values_copy)
In [18]:
print(np.shares_memory(a_values_copy, df))
In [19]:
a_values_copy[0, 0] = 10
print(a_values_copy)
In [20]:
print(df)
In [21]:
a = np.array([[1, 2, 3], [4, 5, 6]])
print(a)
In [22]:
df_a = pd.DataFrame(a, columns=['a', 'b', 'c'])
print(df_a)
In [23]:
print(np.shares_memory(a, df_a))
In [24]:
a[0, 0] = 100
print(a)
In [25]:
print(df_a)
In [26]:
df_a.iat[1, 0] = 10
print(df_a)
In [27]:
print(a)
In [28]:
df_a_copy = pd.DataFrame(a.copy(), columns=['a', 'b', 'c'])
print(df_a_copy)
In [29]:
a[0, 0] = 1
print(a)
In [30]:
print(df_a_copy)