Showing Mixed Values as Donuts

⚠️ Feature in development: This feature is in development and is not yet available on the main MicrobeTrace site.

Mixed-value node coloring makes it possible to distinguish a node containing one categorical value from a node containing several values. A mixed genotype or other mixed categorical value is displayed as a hollow, segmented ring instead of a pie chart.

The colored segments are always divided evenly. They identify which values are present; they do not represent proportions within an individual node.

Although this page uses genotypes as examples, the feature can be used with any node field containing mixed categorical values.

Visual guide

Data represented	Appearance	Meaning
One node with one value	Solid node	One value is associated with one person, sample, or record.
One node with multiple values	Hollow, multi-color ring	Multiple values are associated with one person, sample, or record.
Collapsed group	Filled aggregate pie or bubble with a thicker outline	Multiple nodes have been combined. Pie slices represent the number of nodes in each category.
Collapsed group containing mixed values	Aggregate pie or bubble with only the mixed portion hollow	The hollow portion represents the members with mixed values. Other portions remain solid.

The collapsed group contains three equal outer slices:

• One-third is solid in the color assigned to A.

• One-third is solid in the color assigned to B.

• One-third has a transparent inner portion and an outer ring divided evenly between C and D.

Only the one-third associated with the mixed member is hollow. The other two-thirds remain solid.

The C and D segments indicate that both values occur in the mixed member. Their equal widths do not indicate that C and D occur in equal biological proportions.

If several members have the same mixed label, their combined slice grows according to the number of members. The component colors within that mixed slice remain evenly distributed.

Collapsed groups also include:

• A visibly thicker outer border identifying the node as an aggregate

• Thin black lines between top-level pie slices

• No black inner outline around the hollow portion

Because the hollow part of a collapsed slice is transparent, it may appear white when the visualization or exported image has a white background.

Reading the legend

The legend deliberately uses rectangular swatches rather than miniature node shapes.

• Solid values use the standard single-color swatch.

• Mixed combinations use one rectangular swatch divided into colored stripes.

• The stripe order matches the order used in the nodes.

• The legend does not use hollow rings or donuts.

This keeps the legend consistent with the other color-table entries while still showing every component in a mixed value.

Saving and exporting

Saving the project as a .microbetrace session preserves the mixed-value setting, component colors, and component transparency values.

Normal visualization exports capture the displayed mixed-value styling. Remember that transparent portions of collapsed nodes may appear white in raster exports or other formats that use a white background.

Interpretation guidance

Use the visual shapes as follows:

• Solid means one value in one individual node.

• Hollow and segmented means several values in one individual node.

• Filled and proportionally divided with a thick border means several nodes have been collapsed.

• Partly hollow aggregate means that only some members of a collapsed group contain mixed values.

Do not interpret the equal segments of an individual mixed ring as measured proportions. They are categorical indicators only.

Helpful notes

• Each node is counted once, even when its value contains multiple components.

• Each distinct mixed combination receives its own legend row.

• Equivalent combinations such as A/B and B/A are combined.

• Component colors remain consistent between individual and collapsed nodes.

• Solid and mixed nodes may use the same underlying component colors; the fill treatment distinguishes their meanings.

• The selected node geometry is preserved.

• The setting is off by default, preserving the previous behavior for existing sessions and datasets.

Quick troubleshooting

• The Mixed Values option is missing: Select a field under Color Nodes By. The option is hidden when node coloring is set to None.

• A mixed value still appears solid: Confirm that the option is selected and that the value contains at least two distinct, nonblank components separated by a supported delimiter.

• A value is being split unexpectedly: Check whether its category label contains /, ,, ;, +, |, or the word “and.”

• The colors are unexpected: Open the Node Color Table and edit the stripes in the mixed-value swatch. Also check for inconsistent spelling or capitalization in the source data.

• The component order differs from the source text: This is expected. MicrobeTrace uses a canonical order so equivalent mixtures look the same in every view.

• Only part of a collapsed node is hollow: This is intentional. Only the share belonging to mixed members is hollow.

• An individual node has a white center instead of a transparent center: Individual mixed nodes intentionally use a neutral white center. Transparency is used for the hollow portion of collapsed aggregate slices.

• A transparent aggregate hole looks white: The view or exported image may have a white background. Change the visualization background to confirm that the hole is transparent.

• The hollow center is hard to see: Zoom in or increase the node size. At extremely small on-screen sizes, there may not be enough pixels to display every segment clearly.

Current limitations

• Mixed components are categorical and evenly divided; weighted proportions are not supported.

• MicrobeTrace does not infer a mixture from multiple unrelated columns. The components must appear together in the selected node-color field.

• Separator characters cannot be used literally within a single category name while mixed-value coloring is enabled.

• At extreme zoom levels, very small nodes may not have enough screen pixels to show every color or hollow region clearly.

# Showing Mixed Values as Hollow, Multi-Color Rings

⚠️ Feature in development: This feature is in development and is not yet available on the [main MicrobeTrace site](https://microbetrace.cdc.gov/).

Mixed-value node coloring makes it possible to distinguish a node containing one categorical value from a node containing several values. A mixed genotype or other mixed categorical value is displayed as a hollow, segmented ring instead of a pie chart.

The colored segments are always divided evenly. They identify which values are present; they do not represent proportions within an individual node.

Although this page uses genotypes as examples, the feature can be used with any node field containing mixed categorical values.

Visual guide

Data represented	Appearance	Meaning
One node with one value	Solid node	One value is associated with one person, sample, or record.
One node with multiple values	Hollow, multi-color ring	Multiple values are associated with one person, sample, or record.
Collapsed group	Filled aggregate pie or bubble with a thicker outline	Multiple nodes have been combined. Pie slices represent the number of nodes in each category.
Collapsed group containing mixed values	Aggregate pie or bubble with only the mixed portion hollow	The hollow portion represents the members with mixed values. Other portions remain solid.

Individual mixed nodes have a neutral white center. In collapsed groups, the inner part of a mixed slice is transparent, so the visualization background can be seen through it.

Before you begin

Your node data must contain a field that will be used to color the nodes. For example:

ID	Genotype
Sample 1	2a
Sample 2	3a
Sample 3	2a/3a
Sample 4	6/7a

In this example:

• Sample 1, containing only 2a, is displayed as a solid node.
• Sample 2, containing only 3a, is displayed as a solid node.
• Sample 3 is displayed as a hollow ring divided evenly between the colors assigned to 2a and 3a.
• Sample 4 is displayed as a hollow ring divided evenly between the colors assigned to 6 and 7a.

MicrobeTrace recognizes mixed values separated by:

• A slash: 2a/3a
• A comma: 2a,3a
• A semicolon: 2a;3a
• A plus sign: 2a+3a
• A vertical bar: 2a|3a
• The word “and”: 2a and 3a

Leading and trailing spaces are ignored. Blank, null-like, and N/A components are not drawn as ring segments.

Do not use these separator characters as part of a single category name. MicrobeTrace will interpret the value as mixed.

Enable mixed-value coloring

1. Load the node data and launch a visualization.
2. Open Settings.
3. Open the Styling tab.
4. Under Color Nodes By, select the field containing the values, such as Genotype.
5. Under Mixed Values, select Show mixed values as hollow, multi-color rings.
6. Close the settings panel.

The Mixed Values option appears only after a field has been selected under Color Nodes By.

If the option is not selected, a value such as 2a/3a is treated as one ordinary category and displayed as a solid node.

How mixed rings are calculated

Every distinct component receives its normal category color. The ring is then divided into equal segments.

For example:

• A/B creates two equal segments.
• A/B/C creates three equal segments.
• A/A contains only one distinct component and therefore remains solid.

The segment sizes do not indicate abundance, probability, allele frequency, or any other quantitative proportion. An A/B/C node receives three equal segments even if the underlying data does not contain equal quantities of A, B, and C.

The colored band normally occupies the outer 50% of the node’s radius. MicrobeTrace may make small readability adjustments for narrow or irregular parts of custom shapes.

Consistent ordering

MicrobeTrace uses a consistent component order across the legend and supported visualizations.

Values containing the same components in a different order are treated as the same mixed combination. For example, A/B and B/A use the same colors, segment order, and mixed legend entry.

The existing color-table order is used first. Values that are not already in that order use natural alphanumeric ordering.

Change colors and transparency

The Node Color Table contains entries for solid values and mixed combinations.

A mixed entry uses one rectangular, striped swatch. Each stripe corresponds to one component of the mixed value.

To change its appearance:

1. Show the Node Color Table.
2. Find the mixed value, such as 2a/3a.
3. Select a stripe in its rectangular color swatch to change that component’s color.
4. Use the transparency control beside the swatch to adjust individual component transparency.

Changing a component color updates that component wherever it appears, including:

• Solid nodes with that value
• Other mixed-value rings containing that component
• Mixed portions of collapsed nodes
• Other supported visualization views

The count for a mixed row is the number of nodes containing that mixed combination. Mixed nodes are not counted fractionally in the standalone component rows.

For example, a single A/B node contributes one count to the A/B row. It does not add half a count to A and half a count to B.

Supported views

Mixed-value coloring is displayed consistently across the principal node visualizations.

2D Network

Individual mixed nodes appear as hollow, segmented rings. The ring follows the node’s selected geometry, including custom shapes.

Collapsed groups appear as aggregate pies with a thicker outer border. Thin black lines separate the aggregate slices.

Bubble View

Individual mixed nodes use the same hollow ring treatment as the 2D Network.

When nodes are collapsed within a Bubble group, the resulting aggregate bubble uses proportional slices, a thicker outer border, and thin black separators.

Map View

Individual map markers display the mixed-value ring using the node’s selected shape. Zooming the geographic map does not change the meaning or ordering of its segments.

Map clustering continues to use the existing Map View cluster behavior rather than the collapsed aggregate pies used in 2D and Bubble views.

Phylogenetic View

Mixed leaf nodes have a white center surrounded by evenly divided colored ring segments. The component colors and ordering match the other views.

Custom and irregular node shapes

Mixed-value coloring preserves the selected node shape. It does not replace custom geometry with a circle.

This includes regular and irregular shapes such as:

• Triangles and polygons
• Man and woman icons
• Parasites
• Viruses
• Mosquitoes
• Ticks
• Other custom node geometries

The segmented outer region follows the silhouette of the shape. MicrobeTrace adapts the hollow center to the available interior space so that narrow, concave, or disconnected portions remain recognizable.

At very small rendered sizes, the center may be enlarged slightly to keep the hollow cue visible. The outer colors remain clipped to the original shape.

Mixed values in collapsed groups

Collapsed nodes use a different visual treatment because they represent multiple people, samples, or records.

The aggregate pie represents the proportion of members belonging to each complete category. A mixed member occupies the same proportional share as any other member, but only its share is hollow.

For example, consider a collapsed group containing three nodes:

Member	Value
Person 1	A
Person 2	B
Person 3	C/D

The collapsed group contains three equal outer slices:

• One-third is solid in the color assigned to A.
• One-third is solid in the color assigned to B.
• One-third has a transparent inner portion and an outer ring divided evenly between C and D.

Only the one-third associated with the mixed member is hollow. The other two-thirds remain solid.

The C and D segments indicate that both values occur in the mixed member. Their equal widths do not indicate that C and D occur in equal biological proportions.

If several members have the same mixed label, their combined slice grows according to the number of members. The component colors within that mixed slice remain evenly distributed.

Collapsed groups also include:

• A visibly thicker outer border identifying the node as an aggregate
• Thin black lines between top-level pie slices
• No black inner outline around the hollow portion

Because the hollow part of a collapsed slice is transparent, it may appear white when the visualization or exported image has a white background.

Reading the legend

The legend deliberately uses rectangular swatches rather than miniature node shapes.

• Solid values use the standard single-color swatch.
• Mixed combinations use one rectangular swatch divided into colored stripes.
• The stripe order matches the order used in the nodes.
• The legend does not use hollow rings or donuts.

This keeps the legend consistent with the other color-table entries while still showing every component in a mixed value.

Saving and exporting

Saving the project as a .microbetrace session preserves the mixed-value setting, component colors, and component transparency values.

Normal visualization exports capture the displayed mixed-value styling. Remember that transparent portions of collapsed nodes may appear white in raster exports or other formats that use a white background.

Interpretation guidance

Use the visual shapes as follows:

• Solid means one value in one individual node.
• Hollow and segmented means several values in one individual node.
• Filled and proportionally divided with a thick border means several nodes have been collapsed.
• Partly hollow aggregate means that only some members of a collapsed group contain mixed values.

Do not interpret the equal segments of an individual mixed ring as measured proportions. They are categorical indicators only.

Helpful notes

• Each node is counted once, even when its value contains multiple components.
• Each distinct mixed combination receives its own legend row.
• Equivalent combinations such as A/B and B/A are combined.
• Component colors remain consistent between individual and collapsed nodes.
• Solid and mixed nodes may use the same underlying component colors; the fill treatment distinguishes their meanings.
• The selected node geometry is preserved.
• The setting is off by default, preserving the previous behavior for existing sessions and datasets.

Quick troubleshooting

• The Mixed Values option is missing: Select a field under Color Nodes By. The option is hidden when node coloring is set to None.
• A mixed value still appears solid: Confirm that the option is selected and that the value contains at least two distinct, nonblank components separated by a supported delimiter.
• A value is being split unexpectedly: Check whether its category label contains /, ,, ;, +, |, or the word “and.”
• The colors are unexpected: Open the Node Color Table and edit the stripes in the mixed-value swatch. Also check for inconsistent spelling or capitalization in the source data.
• The component order differs from the source text: This is expected. MicrobeTrace uses a canonical order so equivalent mixtures look the same in every view.
• Only part of a collapsed node is hollow: This is intentional. Only the share belonging to mixed members is hollow.
• An individual node has a white center instead of a transparent center: Individual mixed nodes intentionally use a neutral white center. Transparency is used for the hollow portion of collapsed aggregate slices.
• A transparent aggregate hole looks white: The view or exported image may have a white background. Change the visualization background to confirm that the hole is transparent.
• The hollow center is hard to see: Zoom in or increase the node size. At extremely small on-screen sizes, there may not be enough pixels to display every segment clearly.

Current limitations

• Mixed components are categorical and evenly divided; weighted proportions are not supported.
• MicrobeTrace does not infer a mixture from multiple unrelated columns. The components must appear together in the selected node-color field.
• Separator characters cannot be used literally within a single category name while mixed-value coloring is enabled.
• At extreme zoom levels, very small nodes may not have enough screen pixels to show every color or hollow region clearly.