numpy.nanmin() in Python
Last Updated :
29 Nov, 2018
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numpy.nanmin()
function is used when to returns minimum value of an array or along any specific mentioned axis of the array, ignoring any Nan value.
Syntax : numpy.nanmin(arr, axis=None, out=None)
Parameters :
arr :Input array.
axis :Axis along which we want the min value. Otherwise, it will consider arr to be flattened(works on all the axis). axis = 0 means along the column
and axis = 1 means working along the row.
out :Different array in which we want to place the result. The array must have same dimensions as expected output.Return :Minimum array value(a scalar value if axis is none) or array with minimum value along specified axis.
Code #1 : Working
# Python Program illustrating # numpy.nanmin() method import numpy as np # 1D array arr = [ 1 , 2 , 7 , 0 , np.nan] print ( "arr : " , arr) print ( "Min of arr : " , np.amin(arr)) # nanmin ignores NaN values. print ( "nanMin of arr : " , np.nanmin(arr)) |
Output :
arr : [1, 2, 7, 0, nan] Min of arr : nan nanMin of arr : 0.0
Code #2 :
# Python Program illustrating # numpy.nanmin() method import numpy as np # 2D array arr = [[np.nan, 17 , 12 , 33 , 44 ], [ 15 , 6 , 27 , 8 , 19 ]] print ( "\narr : \n" , arr) # Minimum of the flattened array print ( "\nMin of arr, axis = None : " , np.nanmin(arr)) # Minimum along the first axis # axis 0 means vertical print ( "Min of arr, axis = 0 : " , np.nanmin(arr, axis = 0 )) # Minimum along the second axis # axis 1 means horizontal print ( "Min of arr, axis = 1 : " , np.nanmin(arr, axis = 1 )) |
Output :
arr : [[14, 17, 12, 33, 44], [15, 6, 27, 8, 19]] Min of arr, axis = None : 6 Min of arr, axis = 0 : [14 6 12 8 19] Min of arr, axis = 1 : [12 6]
Code #3 :
# Python Program illustrating # numpy.nanmin() method import numpy as np arr1 = np.arange( 5 ) print ( "Initial arr1 : " , arr1) # using out parameter np.nanmin(arr, axis = 0 , out = arr1) print ( "Changed arr1(having results) : " , arr1) |
Output :
Initial arr1 : [0 1 2 3 4] Changed arr1(having results) : [14 6 12 8 19]