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Preparing Your Data

Quantum XL is flexible about data layout. This page explains how different data types behave in bar charts and helps you prepare your data correctly.

Categorical and Numeric Columns Cannot Be Mixed

When you select a Nominal or DateTime column as a data column, any Continuous, Integer, or Count columns become unavailable (grayed out), and vice versa. This is because Bar Chart processes categorical and numeric data differently — categorical data creates one bar per unique value, while numeric data creates one bar per column.

How Data Types Work

The table below shows what happens when you assign each column type to each role in the Bar Chart dialog. Click a numbered badge to see an example using that configuration.

		Data Column
		Nominal	Continuous	Integer	Count	DateTime
Frequency Column	None	One bar per unique category, sized by count. Only the Count function is available. 1	Each column becomes a bar (column header = bar name). Values are summed by default; all aggregation functions available. 2	Each column becomes a bar (column header = bar name). Values are summed by default; all aggregation functions available.	Each column becomes a bar (column header = bar name). Values are summed by default; all aggregation functions available.	Treated as categorical (see Nominal column)
	Nominal	—
	Continuous	—
	Integer	—
	Count	One bar per unique category, sized by the sum of frequency values (default). All aggregation functions available except Count. 3	Frequency values are used as weights. Each column becomes a bar with a weighted aggregation (sum by default). 4	Frequency values are used as weights. Each column becomes a bar with a weighted aggregation (sum by default).	Frequency values are used as weights. Each column becomes a bar with a weighted aggregation (sum by default).	One bar per unique category, sized by the sum of frequency values (default). All aggregation functions available except Count.
	DateTime	—

— indicates this frequency type is not available for selection

Examples

1 Quick Start — Count occurrences of each category

2 Numeric Data Columns — Summarize numeric columns as bars

3 Count Frequency (Categorical) — Pre-aggregated categorical data with counts

4 Count Frequency (Numeric) — Weighted aggregation of numeric data

GroupBy — Compare segments side by side

Data Layout Options

Categorical Data (One Row Per Observation)

Best for most situations with Nominal or DateTime data. Each row represents a single event or observation.

Defect Type
Scratch
Dent
Scratch
Crack

Quantum XL counts how many times each category appears and creates one bar per category.

Numeric Data (Values in Columns)

Each column of numeric data becomes one bar. The bar height is determined by the selected function (Sum, Mean, Median, etc.).

Q1 Sales	Q2 Sales	Q3 Sales
1250	1380	1520
980	1150	1300

Each column header becomes a bar name. With Sum selected, the bar height is the total of all values in that column.

Pre-Aggregated Data (With Frequency Counts)

Use when your categorical data has already been partially summarized with counts.

Product	Units Sold
Widget A	540
Widget B	210

Select Product as Data Column and Units Sold as Frequency. Quantum XL sums the frequency values for each category.

Common Mistakes

Avoid These Issues

• Forgetting to check Frequency — If your data is pre-aggregated with counts, you must check the count column under Frequency Data. Without it, Quantum XL counts occurrences of each numeric value as a category.
• Missing data — Empty cells in data columns are excluded from analysis.