Re: [ferret_users] different results from Ferret and Matlab

["William S. Kessler" <william.s.kessler@xxxxxxxx>]

On Feb 2, 2013, at 9:23 PM, FISSEHA G. BERHANE wrote:

> Dear Ferreters,
> 
> I have daily precipitation data over a given geographic location. I am getting different mean values of the data in Ferret and in Matlab (5.7mm/day and 7.0 mm/day, respectively). Which is correct, may some one help me with what is the cause of the difference?
> 
> Thank you,
> Fisseha 

Are the timesteps regular? Ferret will recognize if they are not, and @ave will correctly weight the time ranges.

Try plotting the time series with each tool (with the same plot ranges and aspect ratio). Are there differences?

With a simple time series like this, you could simply list a small subset of values (say 10). Compute the mean by hand, then (over the same time range) from Ferret and Matlab. Are these 3 identical? If not, can you see the problem looking at a manageable number of points?

BK