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John, What version of GEMPAK are you running? The gdfile line length is 128 characters, so if you exceed that, you would be out of luck. Then I would suggest making symbolic links from the full names to filea and fileb like you outlined. Another way would be to use the template feature such that you could say gdfile = ruc2|yymmdd/hhnn+ruc2|yymmdd/hhmm Any and all should work (comparing against the current version of 5.7.2) I used (excerpted for relevant parameters here): GDFILE = ruc2|040609/1800+ruc2|040609/1900 GDATTIM = f000 GLEVEL = 500 GVCORD = pres GDPFUN = hght^040609/1900f000+2 ! hght^040609/1800f000+1 TYPE = c CINT = 60 LINE = 6 ! 5 TITLE = 1/-1 ! 1/-2 The above plots the 500mb hghts using the file+1 and file+2 which you would need if you wanted to use fields from either in a computation such as: GDPFUN = sub(hght^040609/1900f000+2,hght^040609/1800f000+1) You can also suceed with the following if you are not requesting fields from both files in one computation: : GDFILE = ruc2|040609/1800 ! ruc2|040609/1900 GDPFUN = hght ! hght Steve Chiswell Unidata User Support >From: John Merrill <address@hidden> >Organization: UCAR/Unidata >Keywords: 200406081443.i58EhCtK014700 >Hello, > Attempting to open multiple files in gdplot2, using >gdfile=filea+fileb, we get Unable to open file filea//...fileb. >Using one file name at a time, we have success. The files happen to be >RUC2 gempak files made from CONDUIT >feed grib files. They are for two run times, differing by 3 hours on the >same day. The file names are specified as full >path names and are thus quite lengthy; they're in a directory well >removed from the one in which gdplot2 is being run. >We've not located a Q&A about this in the email archive. Any >suggestions? Thanks. John > -- NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publically available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.