fn: exprtk.add_variable
[contents]

Contents

Syntax

The syntax for exprtk.add_variable calls is:

f++:  
exprtk.add_variable(params)

n++:  
@exprtk.add_variable(params)

Description

The exprtk.add_variable function is for adding variables to the ExprTk symbol table, it takes a non-zero number of variables which should each be one of the following types:

  • bool
  • int
  • double
  • std::double
  • char
  • string
  • std::vector<double>

Note: With the exception of std::double, variables of the above types are all added to the ExprTk symbol table for you when defined, however if you overload a variable name in a different scope you will need to manually re-add variables you want to use in ExprTk expressions once that scope has been destroyed.

f++ example

Example of exprtk.add_variable being used with f++:

int i=12
for(int i=0; i<10; i+=1){}
exprtk.add_variable(i)
exprtk{!o}(println(i))

Note: If you do not manually re-add the original i back the the ExprTk symbol table then the output of the above example will be 10.00000 rather than the desired 12.00000.

n++ example

Example of exprtk.add_package being used with n++:

@int(i=12)
@for(int i=0; i<10; i+=1){}
@exprtk.add_variable(i)
@exprtk{!o}(println(i))

Note: If you do not manually re-add the original i back the the ExprTk symbol table then the output of the above example will be 10.00000 rather than the desired 12.00000.

Sponsors