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numpy.subtract() function is used when we want to compute the difference of two array.It returns the difference of arr1 and arr2, element-wise.

Syntax : numpy.subtract(arr1, arr2, /, out=None, *, where=True, casting=’same_kind’, order=’K’, dtype=None, subok=True[, signature, extobj], ufunc ‘subtract’) Parameters : arr1 : [array_like or scalar]1st Input array. arr2 : [array_like or scalar]2nd Input array. dtype : The type of the returned array. By default, the dtype of arr is used. out : [ndarray, optional] A location into which the result is stored.   -> If provided, it must have a shape that the inputs broadcast to.   -> If not provided or None, a freshly-allocated array is returned. where : [array_like, optional] Values of True indicate to calculate the ufunc at that position, values of False indicate to leave the value in the output alone. **kwargs : Allows to pass keyword variable length of argument to a function. Used when we want to handle named argument in a function. Return : [ndarray or scalar] The difference of arr1 and arr2, element-wise. Returns a scalar if both arr1 and arr2 are scalars.

Code #1 :

## Python3

 `# Python program explaining``# numpy.subtract() function` `import` `numpy as geek``in_num1 ``=` `4``in_num2 ``=` `6` `print` `("``1st` `Input`  `number : ", in_num1)``print` `("``2nd` `Input`  `number : ", in_num2)``  ` `out_num ``=` `geek.subtract(in_num1, in_num2)``print` `("Difference of two ``input` `number : ", out_num)`

Output :

```1st Input number :  4
2nd Input number :  6
Difference of two input number :  -2```

Code #2 :

## Python3

 `# Python program explaining``# numpy.subtract() function` `import` `numpy as geek` `in_arr1 ``=` `geek.array([[``2``, ``-``4``, ``5``], [``-``6``, ``2``, ``0``]])``in_arr2 ``=` `geek.array([[``0``, ``-``7``, ``5``], [``5``, ``-``2``, ``9``]])`` ` `print` `("``1st` `Input` `array : ", in_arr1)``print` `("``2nd` `Input` `array : ", in_arr2)`` ` `  ` `out_arr ``=` `geek.subtract(in_arr1, in_arr2)``print` `("Output array: ", out_arr)`

Output :

```1st Input array :  [[ 2 -4  5]
[-6  2  0]]
2nd Input array :  [[ 0 -7  5]
[ 5 -2  9]]
Output array:  [[  2   3   0]
[-11   4  -9]]```

#### using for loop:

In this example, we define two lists of numbers called list1 and list2. We then use a for loop to iterate over each index of the lists, and subtract the corresponding elements of the two lists using the – operator. We store each result in a new list called subtraction. Finally, we print the list of results to the console.

## Python3

 `# Define two lists of numbers``list1 ``=` `[``1``, ``2``, ``3``, ``4``, ``5``]``list2 ``=` `[``5``, ``4``, ``3``, ``2``, ``1``]` `# Subtract the elements of the two lists using a for loop``subtraction ``=` `[]``for` `i ``in` `range``(``len``(list1)):``    ``result ``=` `list1[i] ``-` `list2[i]``    ``subtraction.append(result)` `# Print the result of the subtraction``print``(``"The result of the subtraction is:"``, subtraction)`

Output

`The result of the subtraction is: [-4, -2, 0, 2, 4]`

Approach:
The code defines two lists of integers, list1 and list2. It then subtracts the elements of list2 from the corresponding elements of list1 using a for loop, and stores the results in a new list called subtraction. Finally, the result of the subtraction is printed.

Time Complexity:
The time complexity of the for loop is O(n), where n is the length of the input lists list1 and list2. Therefore, the time complexity of the code is O(n).

Space Complexity:
The space complexity of the code is also O(n), because it creates a new list subtraction to store the results of the subtraction operation, which has the same length as list1 and list2. Additionally, it also uses some auxiliary space to store the loop variable and the temporary result of each subtraction operation.

Overall, the code has a linear time complexity and space complexity.

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