Patent ID: 7770072

Claim:
A method of performing fault analysis using numerically coded time series data from a plurality of printers, the method comprising: receiving first time series data for a machine variable for a first printer, wherein the first time series data comprises a plurality of first time entries and an associated first data value for each first time entry; receiving second time series data for the machine variable for a plurality of second printers, wherein the second time series data comprises a plurality of second time entries and an associated second data value for each second time entry; for each second printer: for each first time entry in the first time series data, setting a similarity value associated with the first time entry and an initial second time entry to one minus the square of the difference between the data value for the first time entry and the data value for the initial second time entry; for each second time entry in the second time series data, setting a similarity value associated with an initial first time entry and the second time entry to one minus the square of the difference between the data value for the initial first time entry and the data value for the second time entry; for each first time entry other than the initial first time entry: for each second time entry other than the initial second time entry: setting an intermediate value to one minus the square of the difference between the data value for the first time entry and the data value for the second time entry, and setting a similarity value associated with the first time entry and the second time entry to the maximum of zero, the sum of the intermediate value and the similarity value associated with the time entry preceding the first time entry and the time entry preceding the second time entry, the sum of a penalty value and the maximum similarity value associated with the first time entry, and the sum of a penalty value and the maximum similarity value associated with the second time entry; and setting the similarity measurement to the largest similarity value divided by the smaller of a number of first time entries and a number of second time entries; determining one or more closest matching second printers based on the similarity measurements; and displaying an association between the first printer and each closest matching second printer.