wmean

Weighted Mean or Average

Description

For vectors, WMEAN(X,W) is the weighted mean value of the elements in X using non-negative weights W. For matrices, WMEAN(X,W) is a row vector containing the weighted mean value of each column. For N-D arrays, WMEAN(X,W) is the weighted mean value of the elements along the first non-singleton dimension of X.

Class support for inputs X and W:
   float: double, single

Example:
    x = rand(5,2);
    w = rand(5,2);
    wmean(x,w)

• Acknowledgements: This submission has inspired the following:; Weighted Data Binning [wbin]
• MATLAB release: MATLAB 7.1.0 (R14SP3)

[John D'Errico]

You posted this before, and I found a few problems in it then. All of those problems seems to have been resolved here. My thanks for cleaning this up and resubmitting.

This code has an H1 line. It has clean, readable help. It has error checks for all the errors I'd think to look for. It has internal comments, and it is vectorized.

If I could suggest one thing, I'd suggest that you add a few extra comment lines that include your name, the date the code was last modified, and your e-mail address (if you wish.) You might also note in the website description that this code should run with no problems in older releases of matlab.

[A B]

Comments:
1. For input validation, use assert, or even better - use inputParser.
2. Find can be used with the 'first' or 'last' option.
3. Instead of sum(w.*x,dim), try dot(w,x,dim) as its more abstract.

Comments 1 and 2 above require recent versions of MATLAB.