rakesh kumar

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# How to use numpy array and numpy matrix in django

Creating a Numpy Array:
You can create a numpy array using the np.array() function. Here's an example:

``````import numpy as np

data = [1, 2, 3, 4, 5]
numpy_array = np.array(data)
print(numpy_array)
``````

Output:

``````[1 2 3 4 5]
``````

Checking the Shape of an Array:
You can use the shape attribute to check the shape of a numpy array. Here's an example:

``````import numpy as np

data = [[1, 2, 3], [4, 5, 6]]
numpy_array = np.array(data)
print(numpy_array.shape)
``````

Output:

``````(2, 3)
``````

Checking the Data Type of an Array:
You can use the dtype attribute to check the data type of a numpy array. Here's an example:

``````import numpy as np

data = [1, 2, 3, 4, 5]
numpy_array = np.array(data)
print(numpy_array.dtype)
``````

Output:

int64
Applying Aggregate Functions:
You can use various aggregate functions like sum(), mean(), max(), etc., on numpy arrays. Here's an example:

``````import numpy as np

data = [1, 2, 3, 4, 5]
numpy_array = np.array(data)
print(numpy_array.sum())
print(numpy_array.mean())
print(numpy_array.max())
``````

Output:

``````15
3.0
5
``````

Using the Arrange Function:
The np.arange() function generates a sequence of numbers within a given range. Here's an example:

``````import numpy as np

numpy_array = np.arange(1, 10, 2)
print(numpy_array)
``````

Output:

``````[1 3 5 7 9]
``````

Creating a DataFrame from a Numpy Array:
You can create a pandas DataFrame from a numpy array using the pd.DataFrame() function. Here's an example:

``````import pandas as pd
import numpy as np

numpy_array = np.array([1, 2, 3, 4, 5])
df = pd.DataFrame(numpy_array, columns=['Values'])
print(df)
``````

Output:

``````   Values
0       1
1       2
2       3
3       4
4       5
``````

Accessing Values from a Numpy Array:
You can access specific values from a numpy array using indexing. Here's an example:

``````import numpy as np

data = [[1, 2, 3], [4, 5, 6]]
numpy_array = np.array(data)
print(numpy_array[0, 1])  # Accessing value at row 0, column 1
``````

Output:

2
Reshaping a Numpy Array:
You can use the reshape() function to change the shape of a numpy array. Here's an example:

``````import numpy as np

data = [1, 2, 3, 4, 5, 6]
numpy_array = np.array(data)
reshaped_array = numpy_array.reshape(2, 3)
print(reshaped_array)
``````

Output:

``````[[1 2 3]
[4 5
``````

Create instances of the model and save the data.

``````import numpy as np
from myapp.models import MyModel

data = [1, 2, 3, 4, 5]
numpy_array = np.array(data)

for value in numpy_array:
my_model = MyModel(value=value)
my_model.save()
``````

## numpy multidimensional array

Creating a Numpy Multidimensional Array:
You can create a multidimensional array using the np.array() function and passing a nested list as input. Here's an example:

``````import numpy as np

data = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
numpy_array = np.array(data)
print(numpy_array)
``````

Output:

``````[[1 2 3]
[4 5 6]
[7 8 9]]
``````

Accessing Elements in a Multidimensional Array:
You can access specific elements in a multidimensional array using indexing. Here's an example:

``````import numpy as np

data = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
numpy_array = np.array(data)
print(numpy_array[1, 2])  # Accessing element at row 1, column 2
``````

Output:

``````6
``````

Checking the Shape of a Multidimensional Array:
You can use the shape attribute to check the shape of a multidimensional array. Here's an example:

``````import numpy as np

data = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
numpy_array = np.array(data)
print(numpy_array.shape)
``````

Output:

``````(3, 3)
``````

Checking the Data Type of a Multidimensional Array:
You can use the dtype attribute to check the data type of a multidimensional array. Here's an example:

``````import numpy as np

data = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
numpy_array = np.array(data)
print(numpy_array.dtype)
``````

Output:

``````int64
``````

Applying Aggregate Functions on a Multidimensional Array:
You can apply various aggregate functions like sum(), mean(), max(), etc., on a multidimensional array. Here's an example:
python

``````import numpy as np

data = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
numpy_array = np.array(data)
print(numpy_array.sum())
print(numpy_array.mean())
print(numpy_array.max())
``````

Output:

``````45
5.0
9
``````

Reshaping a Multidimensional Array:
You can use the reshape() function to change the shape of a multidimensional array. Here's an example:

``````import numpy as np

data = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
numpy_array = np.array(data)
reshaped_array = numpy_array.reshape(9)
print(reshaped_array)
``````

Output:

``````[1 2 3 4 5 6 7 8 9]
``````

Transposing a Multidimensional Array:
You can use the T attribute or the transpose() function to transpose a multidimensional array. Here's an example:

``````import numpy as np

data = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
numpy_array = np.array(data)
transposed_array = numpy

print(transposed_array)
``````

Output:

``````[[1 4 7]
[2 5 8]
[3 6 9]]
``````

Sorting a Multidimensional Array:
You can use the `sort()` function to sort a multidimensional array along a specified axis. Here's an example:

``````import numpy as np

data = [[3, 2, 1], [6, 5, 4], [9, 8, 7]]
numpy_array = np.array(data)
sorted_array = np.sort(numpy_array, axis=0)  # Sort along axis 0 (column-wise)
print(sorted_array)
``````

Output:

``````[[3 2 1]
[6 5 4]
[9 8 7]]
``````

Saving Multidimensional Array Data to Django Model:
To save data from a multidimensional array to a Django model, you can follow similar steps as mentioned before for saving a numpy array. Here's an example:

``````import numpy as np
from myapp.models import MyModel

data = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
numpy_array = np.array(data)

for row in numpy_array:
my_model = MyModel(field1=row[0], field2=row[1], field3=row[2])
my_model.save()
``````

In this example, we assume that the MyModel model has fields field1, field2, and field3 to match the columns of the multidimensional array. Adjust the code according to your specific model and field names.