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Hi Robert, First I want to apologize profusely that your question was not answered in a timely manner. It apparently "fell through the cracks" of our procedures adapting to a new support system. I just noticed it and also noticed that it's been over a month since you submitted it. What is the external type of the variable "dateYYYYMMDD"? That is when you display the variable declarations with ncdump, is it declared float, double, or int? If it is declared float, then I think that is the problem. A 32-bit float doesn't have enough precision to represent the floating point value "20030701" exactly, because 32-bit floats only have 23 bits of significance in the fraction, along with 1 sign bit and 8 exponent bits. Even 24 bits can only exactly represent integers up to about 16777216. So it wouldn't help to display such values with more precision, floats are just an inappropriate type for exactly representing dates as 8-digin integers, becasue they are only good for about 7 significant digits. If the variable is declared double, then there is enough precision, but ncdump's default of displaying 15 significant digits for doubles should have displayed the dates correctly. Incidentally, your command ncdump -p 10[,8] 20030701C1.CDF > 20030701C1.CDF.test.txt would not work, because the value of the -p precision option is not specified correctly. the "[, double-digits]" syntax in the reference documentation means that part of the value is optional. So for example, to specify that only 8 significant digits should be displayed for doubles (and 10 for floats), I think what you want is ncdump -p 10,8 20030701C1.CDF > 20030701C1.CDF.test.txt I hope this helps, and that we can provide a much more timely answer to your next question. --Russ Russ Rew UCAR Unidata Program address@hidden http://www.unidata.ucar.edu Ticket Details =================== Ticket ID: CUF-626439 Department: Support netCDF Priority: Critical Status: Open