Changes to the Database format for version 5 GTAP data

The formats of version 5 GTAP data files differ in several ways from previous versions:

•The Parameters file is stored as a HAR file, not a text file. SLUG and RORDELTA are stored as integers, not real numbers.

•GTAP treats international trade margins in a more complete way. On the BaseData file:

•Item VST now of size MARG_COMM*REG was TRAD_COMM*REG.

•New item VTWR size MARG_COMM*TRAD_COMM*REG*REG

•A new vector of reals at header DPSM in BaseData file, size REG, containing 1s (initially); allows more sophisticated cardinalization of national utility.

•Sets file has new header MARG, listing the margin commodities.

•Sets, Parameters, and BaseData files all have a new header DVER, containing the single real number 5.0. This identifies to RunGTAP and other programs that the data matches the version 5 format. RunGTAP refers to this DVER number as the vintage. If the DVER header is missing, RunGTAP assumes that the file is in the previous, version 4 GTAP, format.

The change to file formats going from GTAP 4 to GTAP 5 will be an issue if:

•You attempt to create a new version using data made by the OLD version of GTAPAGG, which creates data for GTAP 4.

•You attempt to load a version archive which was created by an OLD version of RunGTAP, which uses data in GTAP 4 format.

In each case, RunGTAP will detect that the data is in GTAP 4 format (the clue is the absence of the DVER header) and will automatically convert it to the new format the next time a simulation is run. You get a warning when this happens; the old files are saved with HR4 and PR4 extensions.

If some but not all of the Sets , Parameters, and BaseData files have the new header DVER, RunGTAP will stop with an error, issuing the message:

Sets and BaseData files have different vintages

See also New Closure for GTAP version 5.

URL of this topic: www.copsmodels.com/webhelp/rungtap/hc_newgtapfilefmt.htm

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