Usage

The package is designed as to make almost all features of the very flexible EP format (see section ) available to the user. One can and should however, use it in as simple a way as possible. In the following, we give a series of applications ranging from the simplest use to the most complex one. It should be stressed that for the user wanting to use the package as a black box,

• no knowledge of the actual format is required
• the only routines he has to use and understand are

          EPINIT
          EPREAD(EPFHDR,EPFRD)
          EPOUTS
          EPRWND
          EPCLOS
          EPEND

Obviously, the more advanced user will have to learn more.

After the examples, we give a description of all routines in the package, and of the utility routines going with it (which are, however, independent of the package and are intended to fulfil the most common user needs).

While it should not concern most users, the following overview of the format might help to clarify some problems. The basic "units" of information are 16-bit words. However, as of version 1.56, all information including the physical header, maybe given in 32-bit words. The header of each physical record or block is usually 12 words. The user's logical data (or events) can be specified by the user to be in ``units'' of 16 or 32-bit words. Each logical record has a header (normally 4 units long) which specifies the record length and header length in ``units'' and other general identifiers. However, irrespective of the value of "unit" the user can treat the logical data part of the record as 16-bit, 32-bit or packed quantities, by specifying different ``MODES'' to EPREAD and EPOUTS, etc. Packed quantities are applicable to other types of data, for example CDC 60-bit words or 24-bit Camac, but the user has to look after the unpacking himself. The complete description of the format can be found in section .

It should be stressed that the package does not perform automatic number format conversion, but only packs and unpacks (16 and 32-bit words). However, there are conversion routines from and to IBM floating and integer formats and from and to ASCII. To simplify the portability of data between different computer types, 32-bit headers are written in IBM format.

Users are invited to study the examples carefully concerning initialisation, termination, and definition of buffer sizes.