Without seeing your code, all I can suggest is setting a Vendors rating default value to zero, or to a number outside the scope of your rating system (eg -1 or 11 could represent unrated on a scale of 0 to 10, depending on where you want the unrated Vendors to appear)
You would then have a statement set up to print out “unrated” or something else suitable instead of the number.
If this doesnt help, feel free to post the code (in back ticks please) that has got closest to what you want, and we’ll see what we can do.
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