Table of Contents
Use numpy.array() Function
To create an array of the arrays in Python:
- Use the
np.array()function to create anumpy.ndarraytype array of the arrays.
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import numpy as np array1 = np.array([1,2,3]) array2 = np.array([4,5,6]) array3 = np.array([7,8,9]) array = np.array([array1, array2, array3]) print(array) |
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[[1 2 3] [4 5 6] [7 8 9]] |
The Python library NumPy scientifically computes advanced numerical work. It is a language extension that adds support for large, multi-dimensional arrays and matrices in the Python language.
The numpy library provides multi-dimensional array objects that work like arrays in C but with a Python interface. It can therefore act as a bridge between Python and the low-level languages used for scientific computing.
We used the np.array() function to create three arrays: array1, array2, and array3. After we finished generating the arrays, we used the np.array() function to create an arrays of them.
The np.array() function is a general-purpose tool for creating and manipulating arrays in the Python programming language. It converts any iterable object to an array of the same type.
It is not a function in the same sense as len() or str() is, but a factory function or class. The constructor can take any number of arguments. For example, we used the np.array() function to create a numpy.ndarray type array of array1, array2, and array3.
Manually create array of arrays
You can directly create array of arrays by specifying array elements to np.array() method.
Here is an example:
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import numpy as np array = np.array([[1,2,3], [4,5,6], [7,8,9]]) print(array) |
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[[1 2 3] [4 5 6] [7 8 9]] |
Here, we directly passed 2d array to np.array() method to create array of arrays in Python.
Further reading:
Use numpy.append() Function
To generate an array of the array(s) in Python:
- Use the
np.append()function that appends arrays to generate anumpy.ndarraytype array.
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import numpy as np array1 = np.array([1,2,3]) array2 = np.array([4,5,6]) array3 = np.array([7,8,9]) array = np.append(arr=[array1], values=[array2, array3], axis=0) print(array) |
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[[1 2 3] [4 5 6] [7 8 9]] |
We already discussed the numpy library and np.array() function while explaining the code snippet for creating an array of arrays using the numpy.array() function.
The np.append() is a built-in function in the numpy library that adds one iterable object to another in Python. It takes arguments as:
- The
arrto add an iterable at its end. - The
valuesto add at the end ofarr. - The
axisto append the values along. By default, it flattens thearrand thevalues.
We used the np.append() function to append array2 and array3 to the end of array1. In addition, we defined axis=0 to make a multi-dimensional array from the arrays instead of flattening them.