Design Pattern: RM(12) Histograms


A set of incoming alarms has been registered. The human operator would like to compare the number of alarm activations across different dimensions such as priority, typology or time. For each alarm dimension, he would need to know their different ranges.


The human operator needs to compare the number of alarm activations across alarm dimensions and considering data ranges.


Use histograms to depict the frequency distribution of alarm activations. A histogram is a particular type of bar chart that groups data into ranges. Consequently, a rectangle is drawn with height proportional to the count and width equal to the bin size, so that rectangles abut each other.

Known uses
Fig1. DeltaV system alarm summary report
Fig2.Histogram provided by Cisco Prime Central system system

Histograms give a rough sense of the density of the data, and often for density estimation. (Tufte, E. R., & Graves-Morris, P. (1983). The visual display of quantitative information Graphics press Cheshire, CT. )