Tree Map Chart

In This Topic

Tree maps display hierarchical (tree-structured) data as a set of nested rectangles. Each branch of the tree is given a rectangle, which is then tiled with smaller rectangles representing sub-branches. A leaf node's rectangle has two properties - value and change. The value is used to compute the area occupied by the node which is proportional to the value versus the total aggregated value of all leaf nodes in its group. The change value is used to compute the color of the rectangle, which is computed based on the current palette settings and represents the change of the value (absolute or relative to its value).

Tree maps allow you to easily see patterns that would be difficult to spot in other ways, because they present 2D data in an easy to read way. A second advantage of tree maps is that, by construction, they make efficient use of space. As a result, they can legibly display a large number of items on the screen simultaneously.

Settings

Settings

Palette

The settings on this tab allow you to control how the tree map palette is generated.

Smooth Palette - whether to interpolate the colors on the tree map when a change does not fall on a specific color or not.

Change Palette Mode - whether to take the absolute or relative (to its value) change for each node when computing the color of the node.

Palette Range - allows you to specify custom min / max values for the range of values denoted by the palette.

Palette Colors - allows you to specify the Min, Max and Zero colors used to construct the palette.

Layout

The settings on this tab allow you to control the layout of the tree nodes.

Horizontal Fill Mode - specifies how the tree map fills the available space horizontally. Possible options are "Left to Right" and "Right to Left".

Vertical Fill Mode - specifies how the tree map fills the available space vertically. Possible options are "Top to Bottom" and "Bottom to Top".

Sort Order - specifies the order of the nodes. Possible options are "Descending" and "Ascending". "Descending" means that the node with biggest value is placed first, followed by the second largest node etc.

Group / Node Margins and Padding - allow you to specify the margins and padding for group and leaf nodes in the tree.

Group

The settings on this tab allow you to modify the group settings

Fill Style - controls the filling applied on each individual group.

Stroke Style - controls the stroke applied on each individual group.

Label Text Style - controls the label style used to display the group label.

Label Alignment - controls how the label of the group is positioned relative to the group.

Legend Label Format - the format used to display the group on the legend. Possible format strings are:

<label> - the label assigned to the group node

<min_value> - the minimum value of all child nodes in the group

<max_value> - the maximum value of all child nodes in the group

<total_value> - the sum of the values of all child nodes in the group.

<min_change> - the minimum change of all child nodes in the group.

<max_change> - the maximum change of all child nodes in the group.

<min_change_percent> - the minimum change percent of all child nodes in the group.

<max_change_percent> - the maximum change percent of all child nodes in the group.

Label Format - the format used to display the group label. The format settings are the same as the Legend Label Format settings.

Legend

The settings on this tab allow you to control how the tree map is displayed on the legend.

Legend - specifies the target legend

Mode - specifies which nodes must be displayed on the legend. Possible values are:

None - the legend does not display information about the tree map.

Group - the legend displays information about group node only.

Value Nodes - the legend displays information about value nodes only.

Group and Value Nodes - the legend displays information about both group and value nodes.

Palette - the legend displays palette information.

Order - specifies the order in which legend items are added to the legend. Possible values are "Append" and "Prepend".

Content Alignment - specifies how the content of the legend items is aligned.

Text Fit Mode - specifies the text fit mode. Possible options are "Wrap" and "None".

Max Text Width - specifies the maximum text width when Text Fit Mode is set to "Wrap".

Data Requirements

From the values grouping editor you need to specify "Value" and "Change" to be used for each node. The "Id" and "ParentId" are used to specify two columns that are used to create the tree map. The tree construction algorithm is simple:

- assign each node and id taken from the "Id" field.

- for each node make it a child node of the node whose id matches the value "ParentId" field.

Nodes that have child nodes become groups. If a node does not have a parent node it is automatically placed in the root group.