Prerequisite : Introduction to Statistical Functions
Python is a very popular language when it comes to data analysis and statistics. Luckily, Python3 provide statistics module, which comes with very useful functions like mean[], median[], mode[] etc.
mean[] function can be used to calculate mean/average of a given list of numbers. It
returns mean of the data set passed as parameters.
Arithmetic mean is the sum of data divided by the number of data-points. It is a measure of the central location of data in a set of values which vary in range. In Python, we usually do this by dividing the sum of given numbers with the count of number present.
Given set of numbers : [n1, n2, n3, n5, n6] Sum of data-set = [n1 + n2 + n3 + n4 + n5] Number of data produced = 5 Average or arithmetic mean = [n1 + n2 + n3 + n4 + n5] / 5
Syntax : mean[[data-set]]
Parameters :
[data-set] : List or tuple of a set of numbers.
Returns : Sample arithmetic mean of the provided data-set.
Exceptions :
TypeError when anything other than numeric values are passed as parameter.
Code #1 : Working
Python3
import statistics
data1 =
[1, 3, 4, 5, 7, 9, 2]
x = statistics.mean[data1]
print["Mean is :", x]
Output :
Mean is : 4.428571428571429
Code #2 : Working
Python3
from statistics import mean
from fractions import Fraction as fr
data1 = [11, 3, 4, 5, 7, 9, 2]
data2 = [-1, -2, -4, -7, -12, -19]
data3 = [-1, -13, -6, 4, 5, 19, 9]
data4 =
[fr[1, 2], fr[44, 12], fr[10, 3], fr[2, 3]]
data5 = {1:"one", 2:"two", 3:"three"}
print["Mean of data set 1 is % s" % [mean[data1]]]
print["Mean of data set 2 is % s" % [mean[data2]]]
print["Mean of data set 3 is % s" % [mean[data3]]]
print["Mean of data set 4 is % s" % [mean[data4]]]
print["Mean of data set 5 is % s" %
[mean[data5]]]
Output :
Mean of data set 1 is 5.857142857142857 Mean of data set 2 is -7.5 Mean of data set 3 is 2.4285714285714284 Mean of data set 4 is 49/24 Mean of data set 5 is 2
Code #3 : TypeError
Python3
from statistics import mean
dic = {"one":1, "three":3, "seven":7,
"twenty":20, "nine":9, "six":6}
print[mean[dic]]
Output :
Traceback [most recent call last]:
File "/home/9f8a941703745a24ddce5b5f6f211e6f.py", line 29, in
print[mean[dic]]
File "/usr/lib/python3.5/statistics.py", line 331, in mean
T, total, count = _sum[data]
File "/usr/lib/python3.5/statistics.py", line 161, in _sum
for n, d in map[_exact_ratio, values]:
File "/usr/lib/python3.5/statistics.py", line 247, in _exact_ratio
raise TypeError[msg.format[type[x].__name__]]
TypeError: can't convert type 'str' to numerator/denominator
Applications :
Mean/Arithmetic average is one of the very important function, while working with statistics and large values. So, with the function like mean[], trending and featured values can be extracted from the large data sets.