Bubble

Overview

• Type: Three-dimensional chart with X, Y, and Z (bubble size) dimensions
• Dimensions: X-axis (first measure), Y-axis (second measure), Z-axis (bubble size/third measure)
• Use cases: Analyze relationships between three variables, compare entities across multiple dimensions, identify outliers
• Special rules: The “opposite” axis in addGraphAxis becomes the X-axis. Use addGraphBubbleData instead of addGraphData
• Visual: Bubbles positioned by X/Y coordinates, with size representing the third dimension

The image shows a bubble chart displaying employees by age (Y-axis), career length (X-axis), and department size (bubble size), with each department represented as a colored bubble.

Quickstart

To create a Bubble chart, initialize the graph, set up axes (opposite axis = X-axis), and use addGraphBubbleData with three measures.

$olap.addGraph("5", "Employees by Age, Career length and Dept. size", "[key_company]:[department_name]", "","0");
$olap.addGraphAxis('5', '1', 'Avg age','false','20','70','10')
$olap.addGraphAxis('5', '1', 'Avg Career Length','true','0','25','5')
$olap.addGraphBubbleData("5", "1","-", "[department_name]", "round(avg([career_length]),1)", "round(avg([age]),1)", "count(distinct [employee_number])", "", "","")

Start here

Replace:

• "5" with your graph ID
• "[key_company]:[department_name]" with your split element
• The three measures: first = X-axis, second = Y-axis, third = bubble size
• "[department_name]" with your series column for coloring

This produces a bubble chart where each department is a bubble positioned by average career length (X) and age (Y), with size representing number of employees.

Axes setup

Bubble charts require special axis setup: the opposite axis becomes the X-axis.

Required setup:

$olap.addGraphAxis('graph_id', 'axis_id', 'Y-axis Label','false','min','max','interval')
$olap.addGraphAxis('graph_id', 'axis_id', 'X-axis Label','true','min','max','interval')

Important rules:

• First axis (opposite: false) = Y-axis (vertical)
• Second axis (opposite: true) = X-axis (horizontal)
• Always set min, max, and interval to prevent scale changes when filtering

Example:

$olap.addGraphAxis('5', '1', 'Avg age','false','20','70','10')
$olap.addGraphAxis('5', '1', 'Avg Career Length','true','0','25','5')

Caution

The second addGraphAxis call with opposite: true defines the X-axis. This is different from other chart types where the X-axis comes from split_element.

Data series

Use addGraphBubbleData (not addGraphData) with three measures: X, Y, and bubble size.

Syntax:

$olap.addGraphBubbleData(
    "GraphId",
    "AxisId",
    "DataId",
    "Serie",
    "Measure",
    "Measure2",
    "Measure3",
    "Filter",
    "Limit",
    "OrderBy"
)

Parameters:

Parameter	Required	Description	Example
GraphId	Yes	Unique graph identifier	"5"
AxisId	Yes	The axis ID (use same as axes)	"1"
DataId	Yes	Label. Use "-" to inherit from serie	"-" or "Dept: -"
Serie	Yes	Column for coloring bubbles	"[department_name]"
Measure	Yes	X-axis value (first measure)	"round(avg([career_length]),1)"
Measure2	Yes	Y-axis value (second measure)	"round(avg([age]),1)"
Measure3	Yes	Bubble size (third measure)	"count(distinct [employee_number])"
Filter	No	Additional filter expression	"[status] = 1"
Limit	No	Limit number of bubbles (applies to first measure)	"10"
OrderBy	No	Sort by first measure. "M" for descending	"M"

Example:

$olap.addGraphBubbleData("5", "1","-", "[department_name]",
    "round(avg([career_length]),1)",      // X-axis
    "round(avg([age]),1)",                 // Y-axis
    "count(distinct [employee_number])",   // Bubble size
    "", "", "")

Note

Measure order matters: first = X, second = Y, third = size. The series column determines bubble colors.

Size and layout

Control responsive width using setGraphSize. Bubble charts work well at medium to large sizes.

$olap.setGraphSize("graph_id", "XS12", "SM6", "MD6", "LG6")

Recommended sizes:

• Medium: "XS12", "SM6", "MD6", "LG6" (half width)
• Large: "XS12", "SM8", "MD8", "LG8" (two-thirds width)
• Full: "XS12", "SM12", "MD12", "LG12" (full width)

Tip

Bubble charts need space to show relationships clearly. Avoid very small sizes where bubbles overlap too much.

Common patterns

Correlation analysis

Show relationship between two metrics with size as third dimension:

$olap.addGraph("1", "Sales vs Profit", "[region]", "","0");
$olap.addGraphAxis('1', '1', 'Sales','false','0','1000000','100000')
$olap.addGraphAxis('1', '1', 'Profit %','true','0','50','5')
$olap.addGraphBubbleData("1", "1","-", "[region]",
    "sum([profit]) / sum([sales]) * 100",  // X: Profit %
    "sum([sales])",                         // Y: Sales
    "count(distinct [customer_id])",       // Size: Customer count
    "", "", "")

Top N bubbles

Show only largest bubbles:

$olap.addGraphBubbleData("1", "1","-", "[product]",
    "sum([revenue])", "sum([profit])", "sum([quantity])", "", "10", "M");

Performance matrix

Compare efficiency (X) vs volume (Y) with size as impact:

$olap.addGraphBubbleData("1", "1","-", "[department]",
    "avg([efficiency_score])",      // X: Efficiency
    "sum([hours])",                  // Y: Total hours
    "sum([cost])",                   // Size: Cost impact
    "", "", "")

Time-based bubbles

Use time in split element to show evolution:

$olap.addGraph("1", "Performance Over Time", "[month]:[team]", "","0");
$olap.addGraphBubbleData("1", "1","-", "[team]",
    "avg([quality_score])", "avg([speed_score])", "count([tasks])", "", "", "");

Troubleshooting

Bubbles not showing

• Check: You must use addGraphBubbleData, not addGraphData
• Check: All three measures (X, Y, size) must return numeric values
• Check: Verify axis setup with opposite: true for X-axis

Wrong axis mapping

• Issue: Bubbles appear in wrong position
• Fix: Remember: first measure = X-axis, second = Y-axis, third = size
• Fix: X-axis requires opposite: true in second addGraphAxis call

Bubbles too small or too large

• Issue: Size differences not visible
• Fix: Normalize the third measure or use logarithmic scale if appropriate
• Fix: Adjust axis min/max to focus on relevant range

Overlapping bubbles

• Issue: Bubbles obscure each other
• Fix: Use limit to show fewer bubbles
• Fix: Increase chart size with setGraphSize
• Fix: Add filter to focus on specific subset

Axis scale changes when filtering

• Issue: Chart becomes unreadable after filtering
• Fix: Always set explicit min, max, interval in both axes:

  $olap.addGraphAxis('1', '1', 'Y Label','false','0','100','10')
  $olap.addGraphAxis('1', '1', 'X Label','true','0','50','5')

Caution

If you don’t set axis min/max/interval, filtering will auto-scale axes, making comparisons meaningless. Always set fixed scales for bubble charts.

FAQ

Q: Can I use regular addGraphData for bubble charts?
A: No, you must use addGraphBubbleData which accepts three measures (X, Y, size).

Q: Which axis is X and which is Y?
A: The axis with opposite: true is X-axis (horizontal). The axis with opposite: false is Y-axis (vertical).

Q: How do I control bubble colors?
A: Colors come from the Serie column. Different values in that column get different colors.

Q: Can I have multiple bubble series?
A: Yes, call addGraphBubbleData multiple times with different series or filters to overlay multiple bubble groups.

Q: What if my measures have very different scales?
A: Normalize your measures or use calculated percentages. You can also set different axis ranges, but ensure they make sense for comparison.

Q: How do I show labels on bubbles?
A: Use setShowGraphDataLabels with the graph and axis ID. Labels may overlap if bubbles are close.

Q: Can I limit which bubbles are shown?
A: Yes, use the limit parameter in addGraphBubbleData. It applies to the first measure (X-axis).

Q: Why are some bubbles missing?
A: Check filters, NULL values in measures, or if bubbles are outside the visible axis range. Verify all three measures return valid numbers.

Related

• Graph Method Overview - Complete reference for all graph methods
• addGraphBubbleData - Method documentation
• Column - Two-dimensional column charts
• Combined - Mix chart types including bubbles
• Scatter plots - Alternative for X/Y relationships