Spelling of data

Character data are represented as character strings (sequence of characters and blanks) between quotes (in the command scheme and in the command file). SWAN interprets an end of line as an end quote (a character data field can therefore never extend over more than one line).


In a command scheme the character string is always a name (which is placed between quotes as indicated). In the command file such a name can be entered in two ways:

• Replace the name by another character string at the users discretion (between quotes; this is the only occurrence where SWAN is case sensitive; e.g. for text to appear in a plot.
  Example:
  command scheme: KEYword 'City' data
  command file: KEY 'Amsterdam' data
• Copy the name of the variable (without the quotes) literally followed by an = sign and a name at the users discretion (between quotes). SWAN interprets the copied name in the command file as a keyword with all the characteristics of a keyword such as ending a sequence of optional data (see below). As with other keywords the name of the variable is case-insensitive.
  Example:
  command scheme: KEYword 'City' data
  command file: KEY city='Amsterdam' data

As a rule, an error message will result if numerical data is given where character data should be given.


Numerical data are simple numbers, e.g. 15 or $-$7 (integer data), or 13.7 or 0.8E$-$4 (real data). Whether or not integer number or real number should be given by the user is indicated in the description of the command scheme.


Note that a decimal point is not permitted in an integer number. On the other hand, an integer number is accepted by SWAN where a real number should be given.


In a command scheme, the number is always indicated with a name (which is placed between square brackets). In the command file such a name can be entered in two ways:

• Replace the name by a number (not between square brackets).
  Example:
  command scheme: KEYword [nnn]
  command file: KEY 314
• Copy the name of the variable (without the quotes) literally followed by an = sign and the number (not between square brackets). SWAN interprets the copied name in the command file as a keyword with all the characteristics of a keyword such as ending a sequence of optional data (see below). As with other keywords the name of the variable is case-insensitive.
  Example:
  command scheme: KEYword [nnn]
  command file: KEY nnn=314