How to average a column based on another column?

For example, I have a two column data as below:

1945   23.5
1952   25.6
1952   25.9
1952   23.5
1957   26.7
1957   31.2

How do I get a two column data as below, with the left column being the unique numbers: 1945, 1952, 1957, and the second column being the average values of that year:

1945   23.5
1952   25.0
1957   28.95

I can write a loop to do this, but think it must have an easier way to do this.

Thank you@

Answer 1

[Matt Kindig]

This is a good use of accumarray():

[ud,ix,iy]=unique( data(:,1));  
output = [ud, accumarray(iy,data(:,2),[],@mean)];

[Leon]

So cool!

Thank you very much.