Patent US 4,902,469

A display, a display method and an apparatus are disclosed which produce a summary display depicting function states using discrete state bars centered in one window of a two-window display. The status bars represent the states of functions in a process as determined by status decision trees. The discrete states are emphasized by reference lines which indicate the state of each function. Priority among functions is indicated by vertically ranking the bars with the most important function bar appearing at the top. Each bar includes the name of the function, the state of the function and a procedure name for a procedure which can be used to solve the problem identified. The discrete function state is also indicated by the width of the bar and the bar color. On both sides of each bar, a data quality indicator can appear when the quality of the data is less than the best. The other window on the summary display includes meters for the parameters along the active path of the status tree for the most relevant function as determined by the operator.