Compare Mode
Overlay multiple test runs on the same layout to spot differences at a glance — no reconfiguration needed.
What is Compare Mode?
Compare Mode lets you overlay data from multiple test files on every plot of a layout simultaneously. The primary dataset keeps its original style (solid lines), while comparison datasets are displayed with dashed lines in lighter tones. This makes it easy to visually compare acceleration profiles, thermal behavior, or any measured quantity across different test runs.
Typical use cases include comparing a test run against a baseline, evaluating performance before and after a design change, or reviewing repeatability across multiple runs.
How to use it
Open a layout with data
Navigate to your project, open a layout that has at least one slot bound to a dataset. Your plots should already display data.
Click "Compare" in the toolbar
The Compare button is in the top toolbar, next to Autoscale and Sync. Clicking it opens the comparison panel.
Select a dataset to compare
The panel lists all compatible datasets in the project. A compatibility score shows how well channels match. Click a dataset to add it as a comparison overlay.
Review the overlay
All plots in the layout now show both the primary dataset (solid lines) and the comparison dataset (dashed lines). The legend updates to show which trace belongs to which run.
Channel auto-mapping
When you select a comparison dataset, NeydFlow automatically matches channels between the primary and comparison datasets. The matching works in three stages, in order of priority:
| Strategy | How it works | Example |
|---|---|---|
| Exact name | Channels with the same name are matched directly. | vehicle_speed ↔ vehicle_speed |
| Project mapping | If the project has a channel mapping defined (via Project Transforms), renamed channels are resolved. | Vhcl_Spd → mapped to vehicle_speed |
| Similarity | Fuzzy matching by name similarity as a fallback. Requires manual confirmation. | veh_speed_kmh ≈ vehicle_speed |
Tip: If your test files use different channel naming conventions (e.g., OEM-specific names vs. internal standard), set up a Project Mapping first. This ensures Compare Mode matches channels correctly every time.
Managing comparison datasets
Adding multiple datasets
You can compare more than two datasets at once. Each additional dataset gets its own visual style (different dash pattern, shifted hue) so traces remain distinguishable. In practice, comparing 2–3 datasets works best for readability.
Toggling datasets on/off
Each comparison dataset has a toggle in the Compare panel. Turn it off to temporarily hide its traces without removing it from the comparison. This is useful when you want to focus on a specific pair of runs.
Removing a comparison
Click the × next to a dataset in the Compare panel to remove it entirely. Your primary layout is never affected — Compare Mode is purely additive.
Visual differentiation
Compare Mode uses two strategies to distinguish primary data from comparison data:
- Line style: Primary traces use solid lines. Comparison traces use dashed lines.
- Color shift: Comparison traces use a lighter variant of the primary color (e.g., teal → light teal).
The legend at the bottom of each plot shows the dataset name next to each trace, so you always know which run you're looking at.
Readability tip: When comparing 3+ datasets on a plot with many channels, the number of traces can become overwhelming. Consider comparing on a simplified layout with fewer channels per plot, or use the channel toggle to focus on specific measurements.
How it works with CRS
Compare Mode leverages the Channel Reference System (CRS). When a plot references @test:vehicle_speed, Compare Mode creates mirror references for each comparison dataset. The slot binding resolves which dataset provides each trace.
# Primary dataset bound to @test slot
@test:vehicle_speed → run_042/vehicle_speed (solid line)
# Comparison dataset auto-bound to @compare_1
@compare_1:vehicle_speed → run_038/vehicle_speed (dashed line)
This means Compare Mode works with any layout — including those with computed channels. A formula like @test:torque × @test:rpm × π / 30000 is automatically duplicated for each comparison dataset.
API reference
Programmatic access to Compare Mode is available via the REST API.
# Add a comparison dataset to a layout
POST /v1/layouts/{layout_id}/compare
{
"dataset_id": "a22ce6cc-5287-4825-b643-4de6a1c6ef12",
"slot_name": "test",
"mapping_strategy": "auto"
}
# Response includes matched channels and compatibility score
{
"compare_slot": "@compare_1",
"matched_channels": 14,
"total_channels": 16,
"compatibility_score": 0.875,
"unmatched": ["custom_channel_1", "custom_channel_2"]
}See the full API documentation for all parameters and response schemas.