The combination chart is a data visualization that combines the features of the bar chart, line chart, scatter plot, and area chart. The combination chart displays the data using a number of bars, lines, plots, and/or areas, each of which represent a particular category. A combination of different visuals in the same visualization can be useful when comparing values in different categories, since the combination gives a clear view of which category is higher or lower. An example of this can be seen when using the combination chart to compare the sales goals with the actual sales for different time periods.
The combination chart can be found underneath the 'Special charts' section. By drag & dropping it into the canvas, data can be added to the two dataslots ‘Measure’ and ‘X-axis’.
Columns with data type ‘numeric’ are a perfect fit for this slot, as well as ‘hierarchy’ and ‘date time’ which will be aggregated into a single measure based on the number or rows found in the dataset.
The measure slot defines the numeric value of a category and can hold multiple columns. The higher the value the longer the bar, the higher the peak on a line, or dot on a scatter will be. Different aggregations can be set in order to be able to execute different calculations, e.g. Count Rows or Average.
The settings for the combination chart allows you to change how the data is visualized. Bar, area, scatter, or line are the available options.
Columns with data types 'numeric,' ‘hierarchy’, and ‘date time’ are a perfect fit for this slot.
The data added to the category slot defines how many bars - or categories - will appear, as such a dataset with five different values will result in five bars. The measures from the same value will be aggregated into one bar.
The example below demonstrates how a column with datetime (month) data is added to the chart. Without measure data, each bar represents the number of rows per month found in the dataset, which is like the count rows aggregation.
Combining bars and lines in the same visualization can be useful when comparing values in different categories, since the combination gives a clear view of which category is higher or lower.
It is possible to have a second y-axis visualized on the right side of the chart, this axis can be scaled to any of the measures on the chart;
If you're working with a measure of time, the graph will also visualize the days for which there are no measure points (this can be useful for showing future projections);
If you change the measures all to 'lines', then a combination chart will look just like a line chart, but you see all data points in one tooltip when hovering over;
In the chart settings remove or adapt the density and styling of ticks on the axis, replace them with gridlines. Or change the format from Auto to User defined. As such, the label will reflect the exact format of the date level you've chosen (date, month, quarter, etc.).
This chart can be filtered via the Brush filter by default. You can use this filter by clicking and dragging on an area of the chart. The "Clear filter" button will return the dashboard to the initial, unfiltered state. You can also disable the "Brush filter" in the "Interactivity" section of the chart settings.
The legend in this chart can be used to show or hide specific elements by clicking them.