Example 1: convert array to dataframe python
np.random.seed(123)
e = np.random.normal(size=10)
dataframe=pd.DataFrame(e, columns=['a'])
print (dataframe)
a
0 -1.085631
1 0.997345
2 0.282978
3 -1.506295
4 -0.578600
5 1.651437
6 -2.426679
7 -0.428913
8 1.265936
9 -0.866740
e_dataframe=pd.DataFrame({'a':e})
print (e_dataframe)
a
0 -1.085631
1 0.997345
2 0.282978
3 -1.506295
4 -0.578600
5 1.651437
6 -2.426679
7 -0.428913
8 1.265936
9 -0.866740
Example 2: convert dataframe to numpy array
>>> pd.DataFrame({"A": [1, 2], "B": [3, 4]}).to_numpy()
array([[1, 3],
[2, 4]])
Example 3: numpy arrauy to df
numpy_data = np.array([[1, 2], [3, 4]])
df = pd.DataFrame(data=numpy_data, index=["row1", "row2"], columns=["column1", "column2"])
print(df)
Example 4: converting numpy array to dataframe
import numpy as np
import pandas as pd
>>> data = np.array([[5.8, 2.8], [6.0, 2.2]])
>>> print(data)
>>> data
array([[5.8, 2.8],
[6. , 2.2]])
>>> dataset = pd.DataFrame({'Column1': data[:, 0], 'Column2': data[:, 1]})
>>> print(dataset)
Column1 Column2
0 5.8 2.8
1 6.0 2.2
Example 5: list dataframe to numpy array
df.values
array([[nan, 0.2, nan],
[nan, nan, 0.5],
[nan, 0.2, 0.5],
[0.1, 0.2, nan],
[0.1, 0.2, 0.5],
[0.1, nan, 0.5],
[0.1, nan, nan]])