MTS Series 793 - Manual (Page 356)

Note:
The only way to generate hard copies of protected calculations is to use the Calculation Editor’s Print
and Print All functions.
All protected calculations in a given configuration use the same password.
Using protected calculations on stations without this feature
If you load a configuration containing protected calculations on a system that has this feature disabled, the
configuration will still load and run correctly. The Calculation Editor will display the expressions as
“<<Protected>>”, but the toolbar button and the “Protect this expression” check box will not be displayed. In
this situation, you will be able to run the station, but will not be able to see or edit the calculations.
Importing and exporting protected calculations
Protected calculations can be exported and imported between configurations provided the calculation password
in both configurations is identical. Also, when you import and export protected calculations, you do not need
access to the password.
The export feature will write an encrypted string including the current password for protected calculations.
The encryption occurs regardless of whether the calculation editor is currently allowing protected calculations
to be edited. The export feature writes non-protected calculations in clear text.
The import feature can import protected calculations that have been encrypted provided that the current
password in the Calculation Editor is identical to the password used when the calculation was exported. If
the password does not match, an error message is displayed. To import the calculation in this situation, you
must find out the password with which the calculation was exported, then change the current password to
match.
When protected expression text joins with unprotected expression text, the resulting calculation automatically
becomes protected. For instance, when protected expression text is imported into an unprotected calculation,
the resulting calculation becomes protected.
Unnamed Calculations
The outputs of all calculations automatically include formal aliases such as “output0”, “output1”, and so on.
You can add additional informal aliases to any input or output. This allows you to use signals without names
in calculations.
If your script includes a formal call to add a defined list of inputs, you must ensure that the inputs have formal
aliases (“output0”, “output1”, and so on).
Calculation Errors
The following describes the handling of compiler, mathematical, and unrecoverable errors.
Compiler errors
The system will not load a calculation that contains compilation errors (for example, syntax errors, undefined
variables, or mismatched types). The compiler lists the errors it finds, and includes a (line, column) indication
where the error is detected.
However, currently, some errors are not detected until after the code is parsed, and the (line, column) will
point at the end of the code or the function.
356 MTS Series 793 Control Software
Calculated Signals