| 摘要 |
<p>PROBLEM TO BE SOLVED: To easily compare and evaluate even plural pieces of historical trend data whose collection periods differ. SOLUTION: A historical trend setting table 13 where historical trend data names and collection periods are previously registered, a historical trend group setting table 14 where the historical trend data names which are to be displayed on the same graph, and the scale intervals of a time axis, which are simultaneously displayed, are previously registered, a historical trend data collection part 12 collecting data in accordance with setting information, a storage device 15 storing collected data, a time axis adjusting part 16 reading historical trend data which are to be displayed on the same graph and a screen display part 17 that graph-displays only data adjusted to the scale interval of the time axis, which are set and are simultaneously displayed, are installed.</p> |
