| 摘要 |
PROBLEM TO BE SOLVED: To easily compress/restore data on bill information in a short time by setting a difference between individual data on bill information and a reference value to be compression data of individual data and setting the sum of compression data of individual data and the reference value to be restoration data of individual data. SOLUTION: When the compression processing of a designated name is instructed from an operation part 409, reference value data Y of the name to be compressed is taken out from a reference value table. When data corresponding to the compressed name in bill information which is previously inputted to a memory 405 is set to be X, the operation of Z=X-Y is executed, and the difference data Z is stored in the compression data table of the memory 405 as compression data of non-processed data X. When an expansion (restoration) processing is instructed from the operation part 409, the operation of X=Y+Z is executed from reference value data Y of the name and compression data Z corresponding to the name. The operated result, namely, restoration data X is written into an expansion data table (generated on the memory 405). |
