expressions
ARES System Manual: exec Shell
Two built-in commands from the exec shell, if and set, allow for parsing of mathematical operations, called expressions.
For example:
set x = $x + 1
if $y / 2 == 2 then jump my_label
Expressions in
To compare strings, use
if $arg.1 is abort then exit
As with other
There is no operator precedence; expressions are parsed from left to right. Structure your equations accordingly, and use a temporary variable via set for more complex procedures.
Expressions use floating-point evaluation but comparisons will clamp to integer values within ±0.001.
For more sophisticated mathematical facilities, see the lslisp and calc programs.
Two built-in commands from the exec shell, if and set, allow for parsing of mathematical operations, called expressions.
For example:
set x = $x + 1
if $y / 2 == 2 then jump my_label
Expressions in
exec code permit the following operators: !=, ==, <, >, <=, >=, +, -, *, and /.
To compare strings, use
is:
if $arg.1 is abort then exit
As with other
exec commands, $ can be used to retrieve the value of a variable from the env section of the database. See set.
There is no operator precedence; expressions are parsed from left to right. Structure your equations accordingly, and use a temporary variable via set for more complex procedures.
Expressions use floating-point evaluation but comparisons will clamp to integer values within ±0.001.
For more sophisticated mathematical facilities, see the lslisp and calc programs.