AMEND_SYMBOL

This command is for the PARROT module.

The same command is also available for the Gibbs (GES) module.

Interactively calculate the current values of a function or table (predefined by the switched database or previously entered with ENTER_SYMBOL) at the current temperature and pressure condition, and also possible to modify the definitions of variables or functions.

The current values of the temperature and pressure used to calculate the functions or tables are the ones listed with LIST_STATUS. There is no way to change the current temperature and pressure values interactively.

To modify the definitions of entered symbols (variable, functions or parameters), the performance of this command is slightly different one from another, as described below:

  • For variables, the values can be changed.
  • For functions the low and high temperature limits in various ranges (if any), as well the expressions, can be changed.
  • For parameters the low and high temperature limits in various ranges (if any), as well the expressions, can be changed.

Syntax

AMEND_SYMBOL

Prompts

Name: <Symbol name>

Specify the name of an entered symbol.

For tables and functions (or parameters which are treated as functions after these are entered by the ENTER_SYMBOL command with the Parameter keyword, but not by the ENTER_PARAMETER command), after the symbol name is specified here, the program automatically calculates the values under the current temperature and pressure conditions, and lists the current values, such as:

FUNCTION VALUE  2.52500000E+01

TABLE VALUE  1.56000000E+02

For variables and functions (or parameters), there are additional prompts and depend on the symbol type.

 

For a variable, its current value is displayed, and you can change it to a new value:

Value /Current value/: <New value>

For a function (or a parameter entered as a symbol):

Do you want to change the number of ranges /No/:

Enter Y to change the number of ranges for the function, or change some of the temperature limits in the definition, then retype both the low/high temperature limits and functions (see all the remaining details in the ENTER_SYMBOL command.

If you do not want to change it, press <Enter>. The definition of the chosen function in all ranges (if any) is listed, for example:

DIFFERENT FUNCTIONS IN THESE RANGES

298.15<T<2000.00

2000.00<T<4500.00

4500.00<T<6000.00

and this message displays:

Do you want to change range limits /No/:

If a function is different in two or more temperature ranges, you must specify the range of the function of which you want to amend. Or press <Enter> or type 0 to exit this command without making any change.

 

Range number (0 to exit) /0/: <Range number>

Function:

The previous function is available for editing. The editing is performed within the general subroutine FOOLED. This routine prompts as follows:

1:+:>

The prompt consists of the current position in the string and the character at that position between colons (::).