"fi" function in Simulink

Why do I get an error message "Undefined function or variable 'fi'" when I'm using in "fi" function in Simulink for conversion of a numbers to fixed-point? I would like to to note that until now I had no problem using this function. in addition, i can't open my Simulink model.

Please help me, Itai

Answer 1

[Image Analyst]

What does this say

which fi -all

Chances are you don't have a function (in your search path), or variable named that. At least that's what the error message is telling you. If you type ver, what toolboxes/products do you see listed in the command window?

Answer 2

[Walter Roberson]

fi has a bit of a strange history. Formally, it is part of the Fixed Point Designer toolbox, and you need that toolbox in order to use it in some circumstances. But fi is also generated by Simulink in other circumstances even without the Fixed Point Designer toolbox, and the documentation indicates that you should be able to use fi for those particular operations even without the Fixed Point Designer toolbox. The documentation is weak on this point and I have been left uncertain about whether it will work or not.

As Image Analyst indicates, you should use ver to check for the Fixed Point Designer. In particular,

ver('fixedpoint')

will tell you directly whether you have it installed. But you also need to find out whether it is licensed; for that check

license('test','fixed_point_toolbox')

and also use

which -all fi

and if it returns something look towards the end of the line to see whether it says anything about a missing license.