9.2.8 Numeric Comparison with Absolute Tolerance 'FieldComparatorNumericAbs'

9.2.8 Numeric Comparison with Absolute Tolerance '`FieldComparatorNumericAbs`'

This field comparator is for numeric fields, where a given maximal absolute difference can be tolerated. This difference has to be set by the argument max_abs_diff as a positive value. The default value is , i.e. no difference is tolerated.

The agreement weight is returned if the numbers are the same, and the disagreement weight if the absolute difference is larger than the max_abs_diff value. If the absolute difference between the two values is larger than but equal to or smaller than max_abs_diff the partial agreement weight is calculated according to the following formula.

$\begin{eqnarray*} partial\_agreement & = & agree\_weight - \left( \frac{abs\_dif... ...1.0} \right) * \\ ~& ~& (agree\_weight + abs(disagree\_weight)) \end{eqnarray*}$

where the absolute difference between the two values is calculated as

$\begin{displaymath} abs\_diff = abs(value\_A - value\_B). \end{displaymath}$

In its current version no frequency dependent weight calculation is possible, thus the arguments frequency_table, freq_table_max_weight and freq_table_min_weight can not be used with this field comparator function.