The TRANTAB Procedure

Concepts

Understanding Translation Tables and Character Sets
The kth element in a translation table corresponds to the kth element of an ordered character set. For example, position 00 (which is byte 1) in a translation table contains a coded value that corresponds to the first element of the ordered character set. To determine the position of a character in your operating environment's character set, use the SAS function RANK. The following example shows how to use RANK:

data _null_;
   x=rank('a');
   put "The position of a is " x ".";

The SAS log prints the following message: The position of a is 97 .

Each position in a translation table contains a hexadecimal number that is within the range of 0 ('00'x) to 255 ('FF'x). Hexadecimal values always end with an x. You can represent one or more consecutive hexadecimal values within quotation marks followed by a single x. For example, a string of three consecutive hexadecimal values can be written as '08090A'x. The SAS log displays each row of a translation table as 16 hexadecimal values enclosed in quotes followed by an x. The SAS log also lists reference numbers in the vertical and horizontal margins that correspond to the positions in the table. Viewing a Translation Table shows how the SAS log displays a translation table.

Storing Translation Tables
When you use PROC TRANTAB to create a customized translation table, the procedure automatically stores the table in your SASUSER.PROFILE catalog. This enables you to use customized translation tables without affecting other users. When you specify the translation table in the SORT procedure or in a GOPTIONS statement, the software first looks in your SASUSER.PROFILE catalog to find the table. If the specified translation table is not in your SASUSER.PROFILE catalog, the software looks in the SASHELP.HOST catalog.

If you want the translation table you create to be globally accessed, have your SAS Installation Coordinator copy the table from your SASUSER.PROFILE catalog (using the CATALOG procedure) to the SASHELP.HOST catalog.

Modifying Institute-supplied Translation Tables
If an Institute-supplied translation table does not meet your needs, you can use PROC TRANTAB to edit it and create a new table. That is, you can issue the PROC TRANTAB statement that specifies the Institute-supplied table, edit the table, and then save the table using the SAVE statement. The modified translation table is saved in your SASUSER.PROFILE catalog. If you are a SAS Installation Coordinator, you can modify a translation table with PROC TRANTAB and then use the CATALOG procedure to copy the modified table from your SASUSER.PROFILE catalog to the SASHELP.HOST catalog, as shown in the following example:

proc catalog c=sasuser.profile;
   copy out=sashelp.host entrytype=trantab;
run;

You can use PROC TRANTAB to modify translation tables stored in the SASHELP.HOST catalog only if you have update (or write) access to that data library and catalog.

Using Translation Tables Outside PROC TRANTAB

Using Translation Tables in the SORT Procedure

PROC SORT uses translation tables to determine the collating sequence to be used by the sort. You can specify an alternative translation table with the SORTSEQ= option of PROC SORT. For example, if your operating environment sorts with the EBCDIC sequence by default, and you want to sort with the ASCII sequence, you can issue the following statement to specify the ASCII translation table:

proc sort sortseq=ascii;

You can also create a customized translation table with PROC TRANTAB and specify the new table with PROC SORT. This is useful when you want to specify sorting sequences for languages other than U.S. English. The sample program TRABASE from the SAS Sample Library builds transport-format and character-operations translation tables for a number of languages and environments. The NLSSetup Application, shipped with Release 6.11 as part of the SAS Sample Library, provides an easy way to create all the necessary translation tables, device maps, and key maps simply by selecting a country name from a listbox.

See Using Different Translation Tables for Sorting for an example that uses translation tables to sort data in different ways. For information on the tables available for sorting and the SORTSEQ= option, see The SORT Procedure .

Using Translation Tables with the CPORT and CIMPORT Procedures

The CPORT and CIMPORT procedures use translation tables to translate characters in catalog entries that you export from one operating environment and import on another operating environment. You may specify the name of an Institute-supplied or a customized translation table in the TRANTAB statement of PROC CPORT. See TRANTAB Statement in The CPORT Procedure for more information.

Using Translation Tables with Remote Library Services

Remote Library Services (RLS) use translation tables to translate characters when you access remote data.
SAS/CONNECT and SAS/SHARE software use translation tables to translate characters when you transfer or share files between two operating environments that use different encoding standards.

Using Translation Tables in SAS/GRAPH Software

In SAS/GRAPH software, translation tables are most commonly used on an IBM operating environment where tables are necessary because graphics commands must leave IBM operating environments in EBCDIC representation but must reach asynchronous graphics devices in ASCII representation. Specifically, SAS/GRAPH software builds the command stream for these devices internally in ASCII representation but must convert the commands to EBCDIC representation before they can be given to the communications software for transmission to the device. SAS/GRAPH software uses a translation table internally to make the initial conversion from ASCII to EBCDIC. The communications software then translates the command stream back to ASCII representation before it reaches the graphics device.

Translation tables are operating environment-specific. In most cases, you can simply use the default translation table, SASGTAB0, or one of the Institute-supplied graphics translation tables. However, if these tables are not able to do all of the translation correctly, you can create your own translation table with PROC TRANTAB. The SASGTAB0 table may fail to do the translation correctly when it encounters characters from languages other than U.S. English.

To specify an alternative translation table for
SAS/GRAPH software, you can either use the TRANTAB= option in a GOPTIONS statement or modify the TRANTAB device parameter in the device entry. For example, the following GOPTIONS statement specifies the GTABTCAM graphics translation table:

goptions trantab=gtabtcam;

Translation tables used in SAS/GRAPH software perform both device-to-operating environment translation and operating environment-to-device translation. Therefore, a translation table is made up of 512 bytes, with the first 256 bytes used to perform device-to-operating environment translation (ASCII to EBCDIC on IBM mainframes) and the second 256 bytes used to perform operating environment-to-device translation (EBCDIC to ASCII on IBM mainframes). For PROC TRANTAB, the area of a translation table for device-to-operating environment translation is considered to be table one, and the area for operating environment-to-device translation is considered to be table two. See Viewing a Translation Table for a listing of the ASCII translation table (an Institute-provided translation table), which shows both areas of the table.

On operating environments other than IBM mainframes, translation tables can be used to translate specific characters in the data stream that are created by the driver. For example, if the driver normally generates a vertical bar in the data stream, but you want another character to be generated in place of the vertical bar, you can create a translation table that translates the vertical bar to an alternate character.

For details on how to specify translation tables with the TRANTAB= option in SAS/GRAPH software, see
SAS/GRAPH Software: Reference, Version 6, First Edition, Volume 1 and Volume 2.

SAS/GRAPH software also uses key maps and device maps to map codes generated by the keyboard to specified characters and to map character codes to codes required by the graphics output device. These maps are specific to SAS/GRAPH software and are discussed in "The GKEYMAP Procedure" in SAS/GRAPH Software: Reference.

Chapter Contents
Previous
Next
Top of Page