average and standard deviation

I need help writing a program that computes and returns the average and standard deviation of the elements in a vector x, without using the built in mean and std functions.

Answer 1

[Image Analyst]

It's just a simple for loop to sum the variable.

theSum = 0;
for k = 1 : length(x)
  theSum = theSum + x(k);
end
theMean = theSum / length(x);

For the SD, it's very very similar - try it yourself this time. If you need to learn MATLAB, check this out: http://www.mathworks.com/matlabcentral/answers/8026-best-way-s-to-master-matlab