Python _ arithmetic functions

Take the grades list as an example to define the output, sum, average, variance, and standard deviation functions, and output the corresponding values.

Grades = [100,100, 90, 40, 80,100, 85, 70, 90, 65, 90, 85, 50.5] # define the output function def print_grades (grades): for grade in grades: print grade # define the sum function def grades_sum (grades): total = 0 for grade in grades: total + = grade return total # define the average function def grades_average (grades ): sum_of_grades = grades_sum (grades) average = sum_of_grades/float (len (grades) return average # define the variance function def grades_variance (scores): average = grades_average (scores) variance = 0 for score in scores: variance + = (average-score) ** 2 return variance/len (scores) # defines the Standard Deviation Function def grades_std_deviation (variance ): return variance ** 0.5 variance = grades_variance (grades) # Call the function to output the corresponding print print_grades (grades) print grades_sum (grades) print grades_average (grades) print grades_variance (grades) print grades_std_deviation (variance)