Axes in expressions

When creating custom expressions, you might need to refer to an axis from the visualization in the expression. Below is a list of the available axes for different visualization types. Some of the axes can be useful in OVER expressions, whereas others are only used when defining rules or reference lines.

The term axis, in this context, does not only refer to the X and Y axes, but is a general term for the mapping of data to a dimension represented in the visualization: coloring is controlled by the Color axis, marker shape by the Shape axis and so on.

The syntax when referring to axes in an expression is [Axis.Axis Name]. For example, if the Axis Name is "X", the expression should refer to [Axis.X]. Note that the actual names to use may be different in two similar looking visualizations. For example, in the cross table you would refer to Axis.Columns whereas in a heat map you would use Axis.X for similarly set up visualizations.

It does not make any sense to include the axis you are creating the expression for in an OVER expression. Instead, you would probably want to use the categorization on the X-axis or the Color axis when defining an OVER expression on the Y-axis.

Axes to use in OVER expressions and other expressions


Visualization	Axis (property) it represents	Axis name used in expression
Cross table	Columns Rows	Columns Rows
Sparkline	Rows X-axis	Rows* X
Calculated value	Rows	Rows*
Icon	Rows	Rows*
Bullet graph	Rows	Rows*
Bar chart	Category axis Color by	X Color
Line chart	X-axis Color by Line by	X Color Line
Combination chart	X-axis Color	X Color
Pie chart	Color by	Color
Scatter plot	X-axis Y-axis Color by Marker by Shape by Label by Line by	X Y Color Marker Shape Label Line
3D scatter plot	X-axis Y-axis Z-axis Color by Marker by Shape by Label by	X Y Z Color Marker Shape Label
KPI chart	Tile by X-axis	Tile X
Map chart - Feature layer	Color by Geometry by	Color Geometry
Map chart - Marker layer	X-axis Y-axis Color by Marker by Shape by Label by Line by	X Y Color Marker Shape Label Line
Treemap	Hierarchy	Hierarchy
Heat map	X-axis Y-axis	X Y
Parallel coordinate plot	Line by Color by	Line Color
Waterfall chart	Color by Category axis	Color X
Trellis	Columns Rows Pages Panels	Columns Rows Pages Panels

* The Rows axis in a graphical table can be used in OVER expressions in dynamic item columns included in that graphical table.

Example:

Sum([Sales]) OVER (AllPrevious([Axis.X]))

See Using OVER statement to reference data slices and Node navigation for more information about OVER expressions.

Axes to use in rules and reference lines only

When defining rules (for example, for coloring, icons or calculated values) or when setting up a reference line in a visualization, you will define an expression directly using the value on that very axis. (The way to refer to the axes is slightly different in those two contexts.)


Visualization	Axis (property) it represents	Axis name used in expression
Sparkline	Y-axis	Y
Calculated value	Value	Value
Icon	Icon	Icon
Bar chart	Value axis	Y
Scatter plot	X-axis Y-axis	X Y
Line chart	Y-axis	Y
Combination chart	Y-axis	Y
Waterfall chart	Y-axis	Y

Examples in rules:

[Axis.Color]="West"

[Axis.Value]> 10000

Example in reference line:

Avg([Y])*10