Hello Ferret users; I attached an example of a netcdf Jason file which I'm working on ("JA1_IPR_2PcP334_001_20110125_040633_20110125_050240.nc") I'm interested in the sea surface height anomaly (SSHA) and their coordinates (lat, lon), but the file comes with all the data in the time axis (1 pair of coordinates and a measure of SSHA for each scan of the satellite). Here goes the display of the data: 1> ./JA1_IPR_2PcP334_001_20110125_040633_20110125_050240.nc (default) name title I J K L LAT latitude ... ... ... 1:2350 LON longitude ... ... ... 1:2350 SSHA sea surface height anomaly ... ... ... 1:2350, etc I realize I need to regrid it to the "I" and "J" axis to be able to work with it, then, I first tried to regrid the "lat" variable to the "I" axis: define axis/x=1:2350:1 iaxis define grid/x=iaxis gridCOL let lat2=lat[g=gridCOL] But it didn't show any difference on the grid ferret's display: sh grid lat GRID GSF1 name axis # pts start end normal X normal Y normal Z TIME TIME 2350 i 25-JAN-2011 04:06 25-JAN-2011 05:02 sh grid lat2 GRID GSF1 name axis # pts start end normal X normal Y normal Z TIME TIME 2350 i 25-JAN-2011 04:06 25-JAN-2011 05:02 Second I tried to regrid the "lat" variable, but to a grid with the 3 axis: define axis/y=1:2350:1 jaxis define axis/t=1:1:1 laxis define grid/x=iaxis/y=jaxis/t=laxis gridCOL_ROW let lat3=lat[g=gridCOL_ROW] sh grid lat3 GRID (G002) name axis # pts start end normal X normal Y normal Z LAXIS T 1 r 1 1 ...it was worse, ferret and I got more confused...The only way I could work out to give this data a X/Y axis was to save it as a binary: list/clobber/format=unformatted/file="jason1.dat" lon,lat,ssha ...and open it again: define axis/x=1:2350:1 iaxis define grid/x=iaxis gridCOL file/format=unformatted/grid=gridCOL/var=lon,lat,ssha/col=3 "jason1.dat" sh da 2> ./jason1.dat (default) name title I J K L LON LON 1:2350 ... ... ... LAT LAT 1:2350 ... ... ... SSHA SSHA 1:2350 ... ... ... Does anyone have an easier way to regrid the data from the "L" axis to the "I"/"J" axis? After this, I used the "scat2gridgauss_xy" command to put the variables to this global grid: !global grid for all Jason's possible tracks: define axis/x=0:360:0.052252252/UNIT=degrees xJASON define axis/y=-66.15:60.15:0.052252252/UNIT=degrees yJASON let sshaJASON=scat2gridgauss_xy(lon,lat,ssha,x[gx=xJASON],y[gy=yJASON],0.5, 0.5, 2, 0) I ploted these "sshaJASON" variable with "shade", no problems, but isn't there a way to the axis recognize the coordinates described by the variables "lat" and "lon", without the need of the "scat2gridgauss_xy" command? Well, this file is one track of the satellite, and I 'd like to join a hole cycle of it, which is the sum of 254 files, to do so, I made a script in loop, for load and save the 254 binaries files but I'm not able, because Ferret allows until 100 datasets to be loaded at the same time: repeat/i=1:(numberFILES):1 (\ list `i`; \ file/var=ndata "ndata_`i`.txt"; \ define axis/x=1:`ndata[i=1]`:1 iaxis; \ ca da 1; \ define grid/x=iaxis gridTRIPA; \ let arq= "JASON_`i`.dat"; \ file/format=unformatted/grid=gridTRIPA/var=lon,lat,ssha/col=3 "`arq`" ; \ let sshaJASON=scat2gridgauss_xy(lon,lat,ssha,x[gx=xJASON],y[gy=yJASON],0.5, 0.5, 2, 0) ; \ let sshaJASON`i` = missing(sshaJASON,0); \ let sobrepoe`i`_ssha=if (sshaJASON NE 0) then (sshaJASON) else (sobrepoe`i-1`_ssha[l=1]); \ ) let sobrepoe_ssha=sobrepoe(numberFILES)_ssha[l=1] set variable/bad=0 sobrepoe_ssha[l=1] set memo/size=1000;shade sobrepoe_ssha;go land_hires So I tried to cancel the variables ("ca var ssha") at the end of loop, but: **ERROR: invalid command: can only CANCEL variables you DEFINE SSHA ca var ssha then I tried to cancel the dataset at the end of loop ("ca da/all" or "ca da 1"), but it keep asking for the old variable (SSHA), and I'm unabled to use the new variable with the overlappings (sobrepoe_ssha): !-> REPEAT: I=1 !-> list 1 VARIABLE : constant 1.000 !-> SET DATA/EZ/var=ndata "/home/paula/Ressurgencia/JASON/c334/ndata_1.txt" !-> define axis/x=1:2350:1 iaxis Replacing definition of axis IAXIS !-> DEFINE VARIABLE arq= "/home/paula/Ressurgencia/JASON/c334/JASON_1.dat" !-> SET DATA/EZ/format=unformatted/grid=gridTRIPA/var=lon,lat,ssha/col=3 "/home/paula/Ressurgencia/JASON/c334/JASON_1.dat" !-> DEFINE VARIABLE sshaJASON1 = missing(sshaJASON,0) !-> DEFINE VARIABLE sobrepoe1_ssha=if (sshaJASON NE 0) then (sshaJASON) else (sobrepoe0_ssha[l=1]) let sobrepoe_ssha=sobrepoe($cont2)_ssha[l=1] !-> DEFINE VARIABLE sobrepoe_ssha=sobrepoe1_ssha[l=1] set variable/bad=0 sobrepoe_ssha[l=1] shade sobrepoe_ssha **ERROR: variable unknown or not in data set: SSHA shade sobrepoe_ssha Command file, command group, or REPEAT execution aborted Is there any way to clear the datasets so I'm able to handle with new variables? Thanks, Paula Lamosa Nunes |
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JA1_IPR_2PcP334_001_20110125_040633_20110125_050240.nc
Description: Cdf file