! Open the data set. Make a list of time steps to choose for the
sum.
! This can also be a list along another axis, i.e. ZSEQUENCE, and
! then the loop below would be a REPEAT/K=
yes? USE coads_climatology
yes? LET choose = TSEQUENCE({2,3,6,8,9,12})
yes? LET npts = `choose,RETURN=LSIZE`
! Initialize the sum. You might want to use a different initialization
to
! assign missing values to locations where there is never any data.
! On each repeat, make a new variable with the current sum.
yes? LET sum0 = 0*x[GX=sst] + 0*y[GY=sst]
yes? REPEAT/L=1:`npts` (LET ttime = choose[L=`L`]; \
LET sum`L` = sum`L-1` + sst[L=`L`];
\
SHADE sum`l`; PAUSE)
Ansley
Yun.Li@csiro.au wrote:
Dear Ferret users,
I am trying to make a composite image based on some irregular months of an index. For example, I want a composite image of sea level pressure (SLP) based on irregular months such as L=409, 505, 576 and 625 from the following data in ferret.
2> /data/necp/slp_mon_1948_2002
name title I J K L
SLP slp 1:144 1:73 1:1 1:660So far, I can only use the following awkward way to make it, that is,
Let P=(slp[d=2, L=409] + slp[d=2, L=505] + slp[d=2, L=576] + slp[d=2, L=625])/4
Fill PI would appreciate your help on creating the composite image in another simple way based on irregular months, in particular, when the number of irregular months is big.
Best wishes,
Yun
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dr. Yun Li
Environmetrics (www.cmis.csiro.au/envir)
CSIRO Mathematical and Information Sciences
Private Bag 5, Wembley, WA 6913, Australia
Phone: +61 8 9333 6388 Fax: +61 9333 6121
URL: http://www.cmis.csiro.au/Yun.Li/
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
--
Ansley Manke Pacific Marine Environmental Laboratory Seattle
WA