[gradsusr] How to combine the different nc files to calculate the mean and SD? Thanks.

[2008 duan]

Dear Everyone,

        Happy New Year!

        Now I have a question to ask you. Thank you very much!

 'reinit'

'sdfopen D:\TDDOWNLOAD\hgt.1981.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1982.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1983.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1984.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1985.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1986.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1987.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1988.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1989.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1990.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1991.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1992.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1993.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1994.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1995.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1996.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1997.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1998.nc'
'sdfopen D:\TDDOWNLOAD\hgt.1999.nc'
'sdfopen D:\TDDOWNLOAD\hgt.2000.nc'
'sdfopen D:\TDDOWNLOAD\hgt.2001.nc'
'sdfopen D:\TDDOWNLOAD\hgt.2002.nc'
'sdfopen D:\TDDOWNLOAD\hgt.2003.nc'
'sdfopen D:\TDDOWNLOAD\hgt.2004.nc'
'sdfopen D:\TDDOWNLOAD\hgt.2005.nc'
'sdfopen D:\TDDOWNLOAD\hgt.2006.nc'
'sdfopen D:\TDDOWNLOAD\hgt.2007.nc'
'sdfopen D:\TDDOWNLOAD\hgt.2008.nc'
'sdfopen D:\TDDOWNLOAD\hgt.2009.nc'
'sdfopen D:\TDDOWNLOAD\hgt.2010.nc'
'set mpdset hires'
yr=1981
while(yr<=2010)

*******************************************************
*Standard deviation will be caculated
'set lat 0 50.5'
'set lon 119.5 179.5'


'define mean=ave(hgt.'yr',time=01JAN'yr',time=31DEC'yr')'
'define sd=sqrt(ave(pow(hgt.'yr'-mean,2),time=01JAN'yr',time=31DEC'yr'))'

*********************************************************
*This is a skill to plot a shaded map with contour on it
'set grads off'
'set gxout shaded'
'd sd'
'cbarn'
'set gxout contour'
'set cthick 5'
'd sd'
'draw title Standard Deviation of 'yr' '
'printim D:\TDDOWNLOAD\'yr'.png x1000 y800 white'
'c'
yr=yr+1
endwhile
;

I donot know where are the wrongs.  I want to figure out the mean and
SD between 1981 to 2010.

I want to ask how to combine the files containing hgt.1981.nc to
hgt.2010.nc. If it is a single file, I think it is easy to figure out
the mean and SD.

Thank you everyone!


-- 
Weili Duan
Disaster Prevention Research Institute (DPRI), Kyoto University, Uji, Kyoto
611-0011, Japan
TEL: +81-774-38-4131 FAX: +81-774-38-4130
E-mail: duan.scut.cn at gmail.com
           duanwl1986 at flood.dpri.kyoto-u.ac.jp<dyuan.weiri.88r at st.kyoto-u.ac.jp><dyuan.weiri.88r at st.kyoto-u.ac.jp>
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