2.2.3 Charts

The following diagram identifies the major aspects of the file format representation of a chart.

Figure 1: High-level structure of a chart

The chart sheet (section 2.2.3.1) specifies a chart (section 2.2.3.3), a graphic that displays data or the relationships between sets of data in a visual form, and a chart data cache (section 2.2.3.2), a local copy of the data that is used if the chart data is missing or if links to external data sources are broken. The chart specifies one or two axis groups (section 2.2.3.5), a set of axes (section 2.2.3.6) the chart data is plotted against, and the set of series (section 2.2.3.9), trendlines (section 2.2.3.12), and error bars (section 2.2.3.13) specified in the chart. Each axis groups specifies one to four chart groups (section 2.2.3.7) that specify the type of visualization used to display the data. Each series, trendline, and error bar specifies a chart group it is associated with.