Chapter 12

MATLAB Code Examples

function mean = stats(x)
     if ~isvector(x)
          error(‘Input must be a vector’)
     end
     mean = sum(x)/length(x);
end
function [mean, sdev] = stats(x)
     if ~isvector(x)
          error(‘Input must be a vector’)
     end
     len = length(x);
     mean = sum(x)/len;
     sdev = sqrt(sum((x-mean).^2/len));
end

Python Code Examples

import numpy as np

# Function definition is here
def stats( my_array ):
     "This calculates the mean of the input array"
     mean = np.sum(my_array)/np.size(my_array)
     return mean

# Now you can call stats function
m = stats([4,5,6])
print(m)

Exercises

  1. Write a function that calculates the factorial for the input value..
  2. Write a function that calculates the factorial for each value of an input vector, and returns a vector of results.
  3. Write a function that takes an input matrix, and calculates the average value of each row (or – if instructed by an optional argument – the average value of each column) and returns a vector containing the results
  4. Package your functions from these exercises into a custom Python module.