# numpy.ndarray.flat – The NumPy ndarray flat Python Function

## NumPy ndarray flat Function: Introduction

Over N-dimensional arrays, the numpy.ndarray.flat() method is used as a 1 D iterator. Otherwise, it’s a numpy.flatiter instance that isn’t a subclass of Python’s built-in iterator object.

Syntax :

`numpy.ndarray.flat()`

Parameters :

• index : [tuple(int)] index of the values to iterate

Return: 1-D iteration of the array.

## NumPy ndarray flat: Code Examples

Example 01: Working on a 2D array.

``````# welcome to softhunt.net
# Python Program illustrating
# working of ndarray.flat()

import numpy as np

# Working on 1D iteration of 2D array
array = np.arange(15).reshape(5, 3)
print("2D array : \n",array )

# Using flat() : 1D iterator over range
print("\nUsing Array : ", array.flat[2:6])

# Using flat() to Print 1D represented array
print("\n1D representation of array : \n ->", array.flat[0:15])
``````

Output:

Explanation:

• Line1 – imports the NumPy library
• Line2 – Working on the 1D iteration of the 2D array
• Line3 – Prints the Line2 result
• Line3 – Using flat() 1D iterator over range and print it
• Line4 – Using flat() to Print 1D represented array and printing it

Note: These programs will not run in online IDEs. Please test them on your systems to see how they operate.

Example 02: Changing the values of an array

``````# welcome to softhunt.net
# Python Program illustrating
# working of ndarray.flat()

import numpy as np

# Working on 1D iteration of 2D array
array = np.arange(15).reshape(5, 3)
print("2D array : \n",array )

# All elements set to 1
array.flat = 1
print("\nAll Values set to 1 : \n", array)

array.flat[3:6] = 8
array.flat[8:10] = 9
print("Changing values in a range : \n", array)``````

Output:

Note: These programs will not run in online IDEs. Please test them on your systems to see how they operate.

## FAQs

### What is actually numpy.flatiter is?

For each array x, x.flat returns a flatiter iterator. It allows you to iterate across N-dimensional arrays in a row-major manner. Either in a for-loop or by executing its next function.

Let’s have look at the code example. Which shows role of this function.

Example 03: Role of numpy.flatitter()

``````# welcome to softhunt.net
# Python Program illustrating
# working of ndarray.flat()

import numpy as np

# Working on 1D iteration of 2D array
array = np.arange(15).reshape(5, 3)
print("2D array : \n",array )

print("\nID array : \n", array.flat[0:15])

print("\nType of array,flat() : ", type(array.flat))

for i in array.flat:
print(i, end = ' ')``````

Output:

Note: These programs will not run in online IDEs. Please test them on your systems to see how they operate.

### What does flat do in NumPy?

To build a 1-D iterator across the array, use the flat() function. This is a numpy.flatiter instance, which behaves similarly to Python’s built-in iterator object but is not a subclass of it.

## Conclusion

That’s all for NumPy ndarray flat function if you have any confusion contact us through our website or email us at [email protected] or by using LinkedIn. And make sure you check out our NumPy tutorials.

Suggested Articles:

1. numpy.ravel() – The NumPy ravel Python Function