format of function parameter for parsers

[D'Ans]

While testting Levenberd Marquardt nonlinear fit, I noticed that function
parameters are limited to one char + possibly one digit. Ohterwise I get
error -23001 (syntax error of parser).
Is this really true?
Another question: are there tools to generate the model without typing it
all? Handy when the formula gets intricate.
Gerard D'Ans gdans@ulb.ac.be

[BrandonS]

Yes, you are correct. It is in the documentation, but it is a few layers down. Go the the online help for the Levenberd Marquardt VI >> Parse Formula String VI. The formula definition states that "the formula can contain any number of valid variables". There is a link from the word variables to a Formula VI Variables online document. In this docuement, it list all the available variables:

a, a0,...,a9

b, b0,...,b9

.

.

.

z, z0,...,z9

Note: For variable and function names, only lowercase letters are allowed. The VIs interpret capital letters as errors.

[kostya]

As you asked about tools. CalcExpress for LabVIEW toolkit includes formula parser and Levenberg Marquardt fitting VI based on it:
http://www.kshif.com/calcexpress/
It is convenient in use and very fast.
kostya