Converts a sequence of Location features into a vector keeping the top K most common occurrences of each feature (ie the final vector has length k * number of inputs).
keep topK values
min times a value must occur to be retained in pivot
if true ignores capitalization and punctuations when grouping categories
other features to include in the pivot
max percentage of distinct values a categorical feature can have (between 0.0 and 1.00)