Dear ferret users, I want to open some binary files generated by a model in ferret. I have gone throught the users manual and the mail archievs, and tried accordingly. Still I am not able visualized the files correctly in ferret. I am not sure about the fortan codes that generate the files. Here I am attaching two data descriptor files of corresponding binary files. Many thanks in advance for your sugggestions. Jagadish --- Ansley Manke <ansley.b.manke@noaa.gov> wrote: > Hi Martin, > Thank you for writing. We like to know how the > changes we make to > Ferret affect long-time users like you. Well, we > make things more > convenient for some, and unfortunately changing the > output makes things > difficult for others. I'd first like to note that > we have a project in > the works now to give users complete control over > netCDF attributes, > which will make it easier to work with all of the > attributes and control > what is written to your output files. This may > answer much of what > you're asking for. I described a bit more about this > project in a > message not too long ago: > http://www.ferret.noaa.gov/Ferret/Mail_Archives/fu_2005/msg00248.html > > -- With the introduction of the concept of "subspan > modulo" axes we set > Ferret so that an axis with units of degrees > longitude is modulo by > default. This allows us to use different longitude > axes together in > comparisons. What kind of trouble is this causing > you? The Ferret > command to remove the modulo behavior is > > cancel axis/modulo `var,return=xaxis` > > -- The implementation of the bounds attribute is > part of our move > towards adherence to the CF metadata standard. > (http://www.cgd.ucar.edu/cms/eaton/cf-metadata/CF-1.0.html > ). We could > think about adding a qualifier SAVE/NOBOUNDS. I'll > have to think > through whether there are implications of this that > make it undesirable, > but it seems like a simple solution. > > -- First a quick explanation of the use of bounds > when appending time > series. Time axes have an upper bound, seen in the > Ferret > pseudo-variable TBOXHI[gt=var] and a lower bound, > TBOXLO[gt=var]. When > appending more time steps to a time axis, there will > often be a gap > between the last upper bound of the existing data > and the first lower > bound of the new data. If there is, then Ferret > inserts the void > point. (If the new lower bound is less than or > equal to the old upper > bound, no void point is inserted.) We felt this was > a more accurate way > to represent the data. For instance if a year's > monthly data is output, > January through December 2002, and then some data > from the next year, > April through November 2003 is appended, then a void > point is added > whose lower bound is the end of December 2002 and > upper bound is the > start of April 2003. Without this void point, there > is a data point > with a large grid cell: the April 2003 data would > seem to extend from > the start of January to the end of April. > > One could imagine getting something similar to the > old behavior by > defining a time axis with the /EDGES qualifier to > tell Ferret that you > want the first lower bound of the data being > appended to match the upper > bound of the last time from the previous data. > > > Martin Schmidt wrote: > > > Dear Ansley, > > > > I am using ferret 5.8, > > > > FERRET v5.80 Linux(g77) 2.4.20 - 01/03/05 > > 22-Mar-05 16:17 > > > > and found several points, where ferret "knows > better" than it should. > > Opening a netcdf-file > > > > use my_file > > > > and writing one of the variables with (doing > nothing else) > > > > save/clobber/file=my_file.nc my_var > > > > I see, the x-axis is now modulo. > Originally: > > > > float xt_i(xt_i) ; > > xt_i:long_name = "Longitude of T > points" ; > > xt_i:units = "degrees_E" ; > > xt_i:cartesian_axis = "X" ; > > new file: > > double XT_I(XT_I) ; > > XT_I:units = "degrees_east" ; > > XT_I:modulo = 360. ; > > XT_I:point_spacing = "uneven" ; > > XT_I:axis = "X" ; > > XT_I:bounds = "XT_I_bnds" ; > > > > I could cancel the modulo flag, but wouldn't it be > better, if ferret > > leaves the axis definition > > as it is? A previous version (5.4) did not add the > modulo flag. > > > > It also adds always bounds which can be very > disturbing in some cases. > > This cannot be supressed. > > > > The final issue is: > > With previous ferrets one could concatenate files, > which have the same > > grid but an unlimited time axis. It worked simply > by opening file > > after file and writing to an output file. > > This does not work anymore, because ferret adds > void timeslices. > > Indeed the time axis is irregular, but I did > neither specify the > > bounds attribute not used /rigid to get a regular > axis. I could not > > find out, how to get rid of these void points. > > > > Especially for the last point any idea for a > workaround is welcome. > > > > Kind regards, > > Martin Schmidt > > > > > > __________________________________ Do you Yahoo!? Yahoo! Small Business - Try our new resources site! http://smallbusiness.yahoo.com/resources/
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SRF.1997070700.ctl
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