Gxout stat

[Chi Mai Nguyen]

Hi All,

I think I have some suspicion with Grads's output in 'gxout stat' mode. I use version v1.9b4 32-bit.

Sometimes it gives standard deviation equal 0 exactly, which is not right. For example, the output may look like this (please see the last two lines):

Data Type = grid
Dimensions = 1 -1
I Dimension = 1 to 49 Linear 17.5 0.0499992
J Dimension = -999 to -999
Sizes = 49 1 49
Undef value = 9.96921e+36
Undef count = 0  Valid count = 49
Min, Max = 302.61 303.098
Cmin, cmax, cint = 302.55 303.15 0.05
Stats[sum,sumsqr,root(sumsqr),n]:     14844.4 4.49706e+06 2120.63 49
Stats[(sum,sumsqr,root(sumsqr))/n]:     302.947 91776.8 302.947
Stats[(sum,sumsqr,root(sumsqr))/(n-1)]: 309.258 93688.8 306.086
Stats[(sigma,var)(n)]:     0 0
Stats[(sigma,var)(n-1)]:   0 0


Could anyone give me an explanation for that? 

Thank you very much!
Mai
-- 
*********************************
Nguyen Chi Mai
School of Mathematical Sciences
Rm 225, Bld. 28, Clayton Campus
Monash University
Work Ph. +61 3 9905 4458
www.maths.monash.edu.au/~cmnguyen