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# numpy.nanargmin() in Python

• Last Updated : 16 Aug, 2021

The numpy.nanargmin() function returns indices of the min element of the array in a particular axis ignoring NaNs.
The results cannot be trusted if a slice contains only NaNs and Infs.

Syntax:

`numpy.nanargmin(array, axis = None)`

Parameters :

```array : Input array to work on
axis  : [int, optional]Along a specified axis like 0 or 1```

Return :

```Array of indices into the array with same shape as array.shape.
with the dimension along axis removed.```

Code 1 :

## Python

 `# Python Program illustrating``# working of nanargmin()` `import` `numpy as geek` `# Working on 1D array``array ``=` `[geek.nan, ``4``, ``2``, ``3``, ``1``]``print``(``"INPUT ARRAY 1 : \n"``, array)` `array2 ``=` `geek.array([[geek.nan, ``4``], [``1``, ``3``]])` `# returning Indices of the min element``# as per the indices ingnoring NaN``print``(``"\nIndices of min in array1 : "``,``      ``geek.nanargmin(array))` `# Working on 2D array``print``(``"\nINPUT ARRAY 2 : \n"``, array2)``print``(``"\nIndices of min in array2 : "``,``      ``geek.nanargmin(array2))` `print``(``"\nIndices at axis 1 of array2 : "``,``      ``geek.nanargmin(array2, axis ``=` `1``))`

Output :

```INPUT ARRAY 1 :
[nan, 4, 2, 3, 1]

Indices of min in array1 :  4

INPUT ARRAY 2 :
[[ nan   4.]
[  1.   3.]]

Indices of min in array2 :  2

Indices at axis 1 of array2 :  [1 0]```

Code 2 : Comparing working of argmin and nanargmin

## Python

 `# Python Program illustrating``# working of nanargmin()` `import` `numpy as geek` `# Working on 2D array``array ``=` `( [[ ``8``, ``13``, ``5``, ``0``],``           ``[ geek.nan, geek.nan, ``5``, ``3``],``           ``[``10``, ``7``, ``15``, ``15``],``           ``[``3``, ``11``, ``4``, ``12``]])``print``(``"INPUT ARRAY : \n"``, array)` `# returning Indices of the min element``# as per the indices` `'''  ``   ``[[ 8 13  5  0]``   ``[ 0  2  5  3]``   ``[10  7 15 15]``   ``[ 3 11  4 12]]``     ``^  ^  ^  ^``     ``0  2  4  0  - element``     ``1  1  3  0  - indices``'''` `print``(``"\nIndices of min using argmin : "``,``      ``geek.argmin(array, axis ``=` `0``))``print``(``"\nIndices of min using nanargmin :  : "``,``      ``geek.nanargmin(array, axis ``=` `0``))`

Output :

```INPUT ARRAY :
[[ 8 13  5  0]
[ 0  2  5  3]
[10  7 15 15]
[ 3 11  4 12]]

Indices of min element :  [1 1 3 0]```

References :
https://docs.scipy.org/doc/numpy-dev/reference/generated/numpy.nanargmin.html
Note :
These codes won’t run on online-ID. Please run them on your systems to explore the working

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