Floating point conversions are not reversible because of rounding algorithms. That is, converting a field to the alternate format and converting back to the original format does not necessarily return the original value. The conversion routine is triggered each time the ESL program references the external field.

In such cases, it might be best to use the conversion routine only once in each direction. First, copy the data from the field into an ESL variable or a field without a using clause. Do all the manipulations of the data in that internal ESL variable where references will not trigger the conversion routine.