Why do I receive Error -23088 when using the Eval Formula Node.vi (LV6.1)?

[Daniel Ewert]

Hi,
I want to evaluate formulas like x=v>20; with that vi. When typing the
same formula into an normal Formula Node I get the correct answer. When
changing the formula into x=v+20; the eval Formula node.vi works fine.
But whenever I try to resolve a boolean function like that mentioned
above, I receive that f****n Error! Why this? What can I do? Is the Eval
... .vi less powerfull than the normal node?

Thanks for your help,
Daniel

[LabVIEW_Joel]

I think the boolean (binary) ops are the only difference between the two nodes.  I pulled this from the help:

Formula Node and Expression Node Functions

The following list contains the names of the Formula Node and Expression Node functions, and their descriptions. Except for the binary functions, you also can use these functions with Formula VIs. All function names must be lowercase. You also can use operators and the pi constant in Formula and Expression Nodes.

Start at the help above, and see if you can find any helpful information.

J

[Daniel Ewert]

Joel A wrote:
> I think the boolean (binary) ops are the only difference between the two nodes.  I pulled this from the help:
> Formula Node and Expression Node Functions
>
> The following list contains the names of the Formula Node and Expression Node functions, and their descriptions. Except for the binary functions, you also can use these functions with <a href="gmath.chm::/Parser_VIs.html" target="_blank">Formula VIs</a>. All function names must be lowercase. You also can use <a href="mk:@MSITStore:C:\Program%20Files\National%20Instruments\LabVIEW%208.0\help\lvhowto.chm::/Precedence_of_Operators_in.html" target="_blank">operators</a> and the pi constant in Formula and Expression Nodes.
> Start at the help above, and see if you can find any helpful information.
> &nbsp;
> &nbsp;
> J

Thanks for help,
I solved the problem by using the "Parse Arithmetic Expression.llb" from
examples. You can modify it and add the operators you need..