### A Specifications of CONVERT Applications

#### A.1 Explanatory Notes

The Parameters section lists the application’s parameters, with the format:

name  =  type (access)
description

The description entry has a notation scheme to indicate normally defaulted parameters, i.e. those for which there will be no prompt. For such parameters a matching pair of square brackets ([]) terminates the description. The content between the brackets mean

[]
Empty brackets means that the default is created dynamically by the application, and may depend on the values of other parameters. Therefore, the default cannot be given explicitly.
[,]
As above, but there are two default values that are created dynamically.
[default]
Occasionally, a description of the default is given in normal type.
[default]
If the brackets contain a value in teletype-fount, this is the explicit default value.

There is also a Usage entry. This shows how the application is invoked from the command line. It lists the positional parameters in order followed by any prompted keyword parameters using a “KEYWORD=?” syntax. Defaulted keyword parameters do not appear. Positional parameters that are normally defaulted are indicated by being enclosed in square brackets. Keyword (i.e. not positional) parameters are needed where the number of parameters are large, and usually occur because they depend on the value of another parameter. An example should clarify.

ndf2ascii in out [comp] [reclen] noperec=?

IN, OUT, COMP, and RECLEN are all positional parameters. Only IN, and OUT would be prompted if not given on the command line. The remaining parameter, NOPEREC, depends on the value of another parameter (it is FIXED), and will be prompted for when FIXED is TRUE.

The Examples section shows how to run the application from the command line. More often you’ll enter the command name and just some of the parameters, and be prompted for the rest.

Examples give command lines as accepted by the tasks themselves. From the UNIX shell, metacharacters (notably [, ] and ") must be escaped or enclosed in single quotes. For example:

ascii2ndf ngc253q.dat ngc253 q shape=’[100,60]’
fits2ndf ’"abc.fit,def.fits"’ ’fgh,ijk"’ fmtcnv=’"F,T"’ noproexts