After looking at the documentation long enough, I think I understood.
Let's take an example in the documentation where the input data is located:
He PRP B-NP reckons VBZ B-VP the DT B-NP current JJ I-NP account NN I-NP
and function template (in the format %x[row, col] , where row refers to your current position): %x[0,1]
When %x[0,1] expands, depending on the current token, it can scan one of the rows inside the set [PRP, VBZ, DT, JJ, NN] (ie one of the unique rows from the 1st column, where the leftmost column is column 0). For each of these lines, he creates a set of functional functions of the form (looking at the 3rd line of input data):
func1 = if (output = B-NP and feature="U01:DT") return 1 else return 0 func2 = if (output = I-NP and feature="U01:DT") return 1 else return 0 func3 = if (output = O and feature="U01:DT") return 1 else return 0 ...
where this particular line ( DT in the code above) is compared with each individual class.
So, if the output classes are [B-NP, I-NP, O] , the function template extended in the function of the function will look like this:
# row 1 (He, PRP, B-NP) func1 = if (output = B-NP and feature="U01:PRP") return 1 else return 0 func2 = if (output = I-NP and feature="U01:PRP") return 1 else return 0 func3 = if (output = O and feature="U01:PRP") return 1 else return 0 # row 2 (Reckons, VBZ, B-VP) func4 = if (output = B-NP and feature="U01:VBZ") return 1 else return 0 func5 = if (output = I-NP and feature="U01:VBZ") return 1 else return 0 func6 = if (output = O and feature="U01:VBZ") return 1 else return 0 # Row 3 (the, DT, B-NP) func7 = if (output = B-NP and feature="U01:DT") return 1 else return 0 func8 = if (output = I-NP and feature="U01:DT") return 1 else return 0 func9 = if (output = O and feature="U01:DT") return 1 else return 0 # Row 4 (current, JJ, I-NP) func10 = if (output = B-NP and feature="U01:JJ") return 1 else return 0 func11 = if (output = I-NP and feature="U01:JJ") return 1 else return 0 func12 = if (output = O and feature="U01:JJ") return 1 else return 0 # Row 5 (account, NN, I-NP) func13 = if (output = B-NP and feature="U01:NN") return 1 else return 0 func14 = if (output = I-NP and feature="U01:NN") return 1 else return 0 func15 = if (output = O and feature="U01:NN") return 1 else return 0
Regarding where the documentation is mentioned:
The number of functional functions generated by the template is (L * N), where L is the number of output classes and N is the number of unique lines deployed from this template.
In this case, L will be 3, and N will be 5.