Dart Programs to Calculate mean variance and standard deviation

Hi Guy’s Welcome to Proto Coders Point. In this flutter dart programming article let’s understand what is mean variance & standard deviation & how to calculate them in dart programming language.

In data analysis, It’s is very crucial to understand the data tendency. mean, variance & standard deviation are main statistical data measures.

What is Mean, Variance & Standard deviation?

Mean:

Mean is calculated by dividing sum of all the numbers in a given set (array)by the total number of numbers. 

Mean = (Sum of all the observations/Total number of observations)

Variance:

Variance is calculated using mean of the squared differences from the average of the data set (array). It is a statistical measure that quantifies the amount of variability or dispersion within a dataset

variance = s^2 = Σ(xi - x̅)^2 / (N - 1);

xi = each value from the data set.
x̅ = Mean.
N = Number of value in the data set.

Standard Deviation:

is calculated by square root of variance.

SD = sqrt(variance)

Dart Program to find mean variance and standard deviation

Let’s calculate mean, variance & standard deviation using versatile programming language DART.

import 'dart:math';

void main() {
  List<double> data = [0.6, 1.2, 6, 3, 8, 11, 13, 8, 9.3, 9.4];

  // Calculate the mean
  double mean = data.reduce((a, b) => a + b) / data.length;

  // Calculate the variance
  double variance = data.map((x) => pow(x - mean, 2)).reduce((a, b) => a + b) /
      (data.length - 1);

  // Calculate the standard deviation
  double standardDeviation = sqrt(variance);

  print('Mean: $mean');
  print('Variance: $variance');
  print('Standard Deviation: $standardDeviation');
}

Mean: 6.95
Variance: 17.402777777777782
Standard Deviation: 4.171663670261276