#------------------------------------------------------------------------------ # # NSSDC/CDF CDFmerge online help. # # Version 1.0, 25-Jul-06, Raytheon. # # Modification history: # # V1.0 25-Jul-06, M Liu Original version. # V1.1 12-Mar-07, M Liu Populated the help message. # #------------------------------------------------------------------------------ CDFmerge merges two or more CDFs into a single CDF. Edit fields for... Source CDF1: The first CDF to be merged. Source CDF2: The second CDF to be merged. Source CDF3: The third CDF to be merged. Click on the "Select" button to select a desired CDF. One can specify up to 3 CDF files from the GUI. If more than 3 files need to be merged, create a text file containing the name of input files (one CDF on each line) followed by the ouput CDF file name (last line). Provide this text file name in the "Input file name (optional):" box. Output CDF: The file name of the output file. Input file name (optional): The name of the input text file. If more than 3 files need to be merged, create a text file containing the name of the input files (one CDF on each line) followed by the ouput CDF file name (last line). Provide this text file name in this box. Example: cdf1.cdf cdf2.cdf . . cdfN.cdf my_merged.cdf Master CDF/file (optional): Specifies to use the value of the global attributes in the master CDF file (master_CDF) or text file (master_text) instead of getting the value of the global attributes. Some attributes in the master_CDF or master_text are also used to construct the merged file name. The given master file name is checked first to see if it is a CDF file (master_CDF). If it is not a CDF file, then it is treated as a mater text file (master_text). If a global attributed named "File_naming_convention" exists in the master_CDF or master_text, its value and pattern are used to construct the leading portion of the output file name. Also, a time stamp and data version are added to the output file name. The Epoch or Range_epoch data from source CDFs are checked to determine the time stamp. The Data_version attribute is used for calculating the data version number. If the File_naming_convention attribute does not exist, then the Logical_file_id attribute is used to construct the output file name. The timestamp portion of the file name is updated from the source CDFs's Epoch/Range_epoch data. If the Logical_file_id attribute doesn't exist, the program will search for the existence of the following attributes in the order specified here to construct the output file name: Source_name, Descriptor, and Data_type. If any of these attributes is missing or its entry doesn't exist, an error is issued as the output file name can not be determined. Syntax for : Global attribute name on a separate line followed by a colon (:). The value(s) of the global attribute are specified on separate line(s), one global attribute entry per line, immediately after the global attribute name. The following example illustrates how to specify/override the value of the Logical_file_id, Logical_source, and Instrument_type global attributes: Line 1) Logical_file_id: Line 2) tha_l1_fgm_20060816_v01 Line 3) Line 4) Logical_file_source: Line 5) tha_l1_fgm Line 6) Line 7) Instrument_type: Line 8) FGE Line 9) FGM If this option is used, the "Merge Data Only" option is automatically turned on. Prefixes for source CDFs (optional): Specifies to use the user provided prefixes instead of the default prefixes. Prefixes should be separated by a comma (,) without sapces (e.g. p1,p2,p3), and the number of prefixes must match the number of input/soucrce CDFs. The first prefix followed by a underscore (_) is added to the beginning of each variable and global attribute in the first input CDF, the second prefix is added to the variables and global attributes in the second CDF, and so on. If this option is specified, prefixes, separated by a ",", The maximum length of each prefix is 20 characters. Check boxes for... About: Display the library version that tool uses. No prefix: Specifies not to add prefixes to the variables in the merged file. See "Prefixes for source CDFs (optional)" for more detailed information on the prefixes. If this option is specified, each variable name in the source CDFs is unique (CDF doesn't allow duplicate variable name). If there is a duplication variable, the merge process will abort. This option can not be used with the "Prefixes for source CDFs (optional)" option. Merge Data Only: If this option is selected, the merged file will not have a separate variable for each variable in the source CDFs. Variables with the same name from the source CDFs will be combined into one, keeping the same name without prefix in the merged file. The merged file will have the meta-data, i.e., global and variable attributes, from the first source CDF. Since variable data will be combined in the order specified in the source CDFs, it's important to arranage the source files in a proper sequence (if they are sequence-sensitive). CDAWeb: Specifies to create a merged file that is ISTP/CDAweb CDF compliant. The ISTP/CDAweb guideline is available at http://spdf.gsfc.nasa.gov/istp_guide/istp_guide.html. The 'epoch' variable is a mandatory variable in the ISTP/CDAweb guideline. Thus, the duplication of this variable is allowed in the input CDFs. The duplication of the variable named "RANGE_EPOCH" (in any upper/lower case combination) is also allowed. Augment_Label: Specifies to create a variable attribute named AUGMENT_LABL and set its value to "TRUE" for all variables. Buttons for... Enter Causes CDFmerge to merge the requested CDFs. Help Causes this online help to be displayed. Quit Exits CDFmerge.