formatting a list to drive a line object

hi everyone,

i'd like to sweep a sine tone from one specified frequency to another specified frequency, in a certain number of seconds.

i'd like all three parameters to be things i can just type into a number box and hit "go".

seems simple enough, but i can't figure out how to format these three number boxes into a message that [line] understands. maybe just because the comma is missing between the first value and the second value?

the patch here isn't working: the comma isn't being appended to the first value as i'd hoped.

could someone give me a hint to point me in the right direction?

many thanks!

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