VAR - Variable Assignment

PURPOSE

Assign values to Register (Numeric) or Symbolic (String) variables.

SEE ALSO

FR L	[Read (sets) a local string (symbolic) variable]
FR G	[Read (sets) a global string (symbolic) variable]
FR LS	[Sets local string variable using current string values]
FR GS	[Sets global string variable using current string values]
RR G	[Read Register variables - Global]

USAGE

.OPERATION: [varname] = number

    <or>
[varname] = 'chars'
    <or>
[varname] = [old-varname]
    <or>
[varname] = 'opt-chars'[varname]'opt-chars'
    <or>
GLOBAL [varname] = 'chars'
    <or>
GLOBAL [varname] = number

[Where:

[varname]

Numerical (register) or string (symbolic) variable name which will be assigned a value. Variable names must start with an alphabetical letter and can contain the 36 alphanumerical characters, '-', and '_'. The [] brackets are necessary.

'chars'

A character string to be associated with the string (symbolic) variable. The quotes are necessary.

number

A numerical value to be associated with the numerical (register) variable.

[old-varname]

The name of an existing numerical (register) or string (symbolic) variable . The [] brackets are necessary. If [old-varname] is a string variable and [varname] does not already exit then [varname] will also be a string variable.

'opt-chars'

An optional character string to be become part of the string (symbolic) variable. The quotes are necessary.

GLOBAL

An optional flag indicating that he variable is visable in all procedures following its definition.

A 'chars' or 'opt-chars' can have embedded blanks or double (") quotes.

Anything within a 'chars' is evaluated (bound) only when the string is used.

Anything within an [old-varname] not surrounded by quotes is evaluated when variable is created (NOT used).

Some typical examples:

   [str_variable] = 'filename'
   [str_variable] = 'img{***[reg-variable]}'
   [str_variable] = 'img[old-str-variable]'
   [str_variable] = 'IMG{***[old-str-variable]}'
   [str_variable] = [old-str-variable]
   global [str_variable] = 'filename'
   GLOBAL [str_variable] = 'filename'

   [reg_variable] = 10
   [reg_variable] = 45.7*32
   [reg_variable] = -1.5678E-02
   GLOBAL [reg_variable] = -2.567

Some more complex examples:

   [new_str_variable] = '[old-str-variable]dat'
   [new_str_variable] = [old-str-variable]'.dat'
   [new_str_variable] = 'IMG'[old-str-variable]
   [new_str_variable] = 'IMG'{***[old-reg-variable]}'
   [old_str_variable] = 'temp-dir/'[old-str-variable]

NOTES

1. GLOBAL register variables can only be created/modified by a GLOBAL [varname] = number or the obsolete: 'RR G' operations. 'DO', 'UD', and 'UD IC', can not create/set a global register variable. This restriction is necessary to preserve backward compatibility.

SUBROUTINES

SYMPAR, SETSYMPAR, SUBSYMPAR, GETNEXTTOKEN

CALLER

SPIDER

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