fields = replaceFields(fields,FieldName1,FieldValue1,...,FieldNameN,FieldValueN)changes the existing fields in each header field with the specified names to the indicated values and returns the updated array. This method is the same aschangeFields, but if a field does not exist, thenreplaceFieldsadds it to the end of fields.

fields = replaceFields(fields,newFields)changes the existing fields in each header field to the names, values, and types specified infields. This syntax might change the class of an existing field if the field name is a case-insensitive match to a name infields.