Python | Flatten a 2d numpy array into 1d array

Given a 2d numpy array, the task is to flatten a 2d numpy array into a 1d array. Below are a few methods to solve the task.

Method #1 : Using np.flatten()

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# Python code to demonstrate
# flattening a 2d numpy array
# into 1d array
  
import numpy as np
  
ini_array1 = np.array([[1, 2, 3], [2, 4, 5], [1, 2, 3]])
  
# printing initial arrays
print("initial array", str(ini_array1))
  
# Multiplying arrays
result = ini_array1.flatten()
  
# printing result
print("New resulting array: ", result)

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Output:


        
          
          
          
        

            

initial array [[1 2 3]
 [2 4 5]
 [1 2 3]]
New resulting array:  [1 2 3 2 4 5 1 2 3]





 

Method #2:  Using np.ravel()











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# Python code to demonstrate 


# flattening a 2d numpy array 


# into 1d array 


  


import numpy as np 


  


ini_array1 = np.array([[1, 2, 3], [2, 4, 5], [1, 2, 3]]) 


  


# printing initial arrays 


print("initial array", str(ini_array1)) 


  


# Multiplying arrays 


result = ini_array1.ravel() 


  


# printing result 


print("New resulting array: ", result) 



















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Output:


initial array [[1 2 3]
 [2 4 5]
 [1 2 3]]
New resulting array:  [1 2 3 2 4 5 1 2 3]





 

Method #3: Using np.reshape()











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# Python code to demonstrate 


# flattening a 2d numpy array 


# into 1d array 


  


import numpy as np 


  


ini_array1 = np.array([[1, 2, 3], [2, 4, 5], [1, 2, 3]]) 


  


# printing initial arrays 


print("initial array", str(ini_array1)) 


  


# Multiplying arrays 


result = ini_array1.reshape([1, 9]) 


  


# printing result 


print("New resulting array: ", result) 



















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Output:


initial array [[1 2 3]
 [2 4 5]
 [1 2 3]]
New resulting array:  [[1 2 3 2 4 5 1 2 3]]






          
          
          
          

            

    

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