Harmonic Mean of a distribution:
Harmonic Mean is the reciprocal of mean of reciprocal values in the distribution.
Harmonic Mean of the distribution is given by the formula
X H = n / ∑ (1/Xi)
when Xi > 0 for i = 1,2,3......n
Examples of Harmonic Mean:
- Cost Averaging
- Travelling a constant distance "d" by breaking the distance as
d1, d2,...dn, travelling each distance with a different velocity and finally
finding out a uniform velocity that would have required to travel the entire
distance with the same total time is nothing but finding the harmonic mean
of the velocities.
harmonic_mean() function from the statistics module of python standard library, returns the harmonic mean of the distribution which is also called as the subcontrary mean of the distribution.
Example Python Program to find the Harmonic Mean of a distribution:
# velocities of individual distances
velocityData = [50,55,65,60]
# Find harmonic mean
harmonicMean = statistics.harmonic_mean(velocityData)
#print the harmonic mean with a precision of upto 2 decimal points
print("The harmonic mean of velocities is:%.2f"%(harmonicMean))
Output of the Python Program that finds the Harmonic Mean of a distribution:
The harmonic mean of velocities is:56.95