In this article, we will discuss how to calculate the mode of the Numpy Array.
Mode refers to the most repeating element in the array. We can find the mode from the NumPy array by using the following methods.
Method 1: Using scipy.stats package
Let us see the syntax of the mode() function
Syntax :
variable = stats.mode(array_variable)
Note : To apply mode we need to create an array. In python, we can create an array using numpy package. So first we need to create an array using numpy package and apply mode() function on that array. Let us see examples for better understanding.
Example 1:
Applying on 1-D array
Python3
# importing required packagesfrom scipy import stats as stimport numpy as np# creating an array using array() methodabc = np.array([1, 1, 2, 2, 2, 3, 4, 5])# applying mode operation on array and# printing resultprint(st.mode(abc)) |
Output :
ModeResult(mode=array([2]), count=array([3]))
Example 2:
Applying on a 2-D array
Python3
# importing required modulesimport numpy as npfrom scipy import stats as st# creating a 2-D array using numpy packagearr = np.array([[1, 2, 3, 4, 5], [1, 2, 2, 2, 2], [4, 5, 7, 9, 4], [6, 7, 8, 9, 2], [2, 3, 4, 8, 6]])# applying mode operation and printing the# resultprint(st.mode(arr)) |
Output :
ModeResult(mode=array([[1, 2, 2, 9, 2]]), count=array([[2, 2, 1, 2, 2]]))
Method 2: Using Statistics module
Like NumPy module, the statistics module also contains statistical functions like mean , median , mode….etc . So let us see an example of a mode using the statistics module.
Example :
Python3
import statistics as stimport numpy as np# create an 1 d arrayarr1 = np.array([9, 8, 7, 6, 6, 6, 6, 5, 5, 4, 3, 2, 1, 1, 1, 1, 1, 1])# display the modeprint(st.mode(arr1)) |
Output :
1
Method 3: Using user-defined Function
Here we are not using any predefines functions for getting mode of a series. Let us see an example with demonstrates how to calculate mode without predefined functions.
Example :
Python3
# creating a listlst = [1, 2, 3, 4, 5, 6, 2, 3, 4, 5, 5, 5, 5]# defining a function to calculate mode. It# takes list variable as argumentdef mode(lst): # creating a dictionary freq = {} for i in lst: # mapping each value of list to a # dictionary freq.setdefault(i, 0) freq[i] += 1 # finding maximum value of dictionary hf = max(freq.values()) # creating an empty list hflst = [] # using for loop we are checking for most # repeated value for i, j in freq.items(): if j == hf: hflst.append(i) # returning the result return hflst# calling mode() function and passing list# as argumentprint(mode(lst)) |
Output :
[5]
