Measurement ratio filter....need to check for 'divide by zero' error

[pbr6cornell]

the measurement ratio filters (low range ratio and high range ratio) do not check for if the range value > 0, so can hit divide-by-zero errors. Need to perfrorm error check so query doesn't fail.

Work-around for the time-being: I added extra criteria that requires value_as_number > 0 and high_range > 0.