Overview
The Scenario Tab Bar sits below the Top Bar and lets you work with multiple scenario files at the same time. Each open scenario has its own tab; the bar also provides a home button and, in the desktop app, a folder picker.
| Control | Function |
|---|---|
| Folder icon | Opens a system folder picker to select your scenarios directory. Shown in the desktop app only. |
| Home icon | Returns to the welcome state (no scenario loaded). Always visible. |
| Scenario tabs | Each tab represents an open scenario. Click a tab to make it active. A blue dot marks a scenario held in memory; a red ring marks an evicted scenario that can be reloaded; a pulsing accent bar shows the active scenario is still loading. Italic tab name indicates a temporary (unsaved) scenario. |
| × (close button) | Closes that scenario tab. Appears on hover or keyboard focus. |
| + (new tab) | Opens a new empty scenario tab. Sticky at the right edge of the tab strip. |
| N/3 counter | Shows how many of the three available in-memory slots are in use. Turns blue when all three slots are occupied. |
| Series Summary | Opens the Series Summary panel. |
In-Memory Scenario Slots
Apollo holds open scenarios in memory so you can switch between them instantly. The N/3 counter shows how many of your available in-memory slots are currently in use. When the counter turns blue (or accent colour), all slots are full.
What "held in memory" means: A scenario held in memory has its simulation data (CSV files) already loaded. Switching to it is instant — no reload from disk. A scenario that is open (visible as a tab) but not held in memory shows a red ring indicator on its tab. Clicking it reloads the scenario from disk.
When a slot is needed for a new scenario: Before opening a new scenario when all slots are full, Apollo shows a warning dialog:
"Opening [new scenario name] will unload [oldest open scenario] from memory. [Oldest scenario] will remain in your tab bar and reload automatically when you click it."
Is work lost when a scenario is evicted? No. Eviction only releases the CSV data from memory. The scenario tab stays visible. Clicking the tab reloads the data from disk — no simulation re-run is needed and no user edits to the scenario are lost.
What reload costs: Re-reading the CSV output files from local disk. The reload time depends on scenario size. There is no re-simulation; the scenario data was written to disk during the original run.
Changing the slot count: The default is 3. You can change this in Settings → Dashboard Settings → Preloaded scenarios (radio buttons 1–5). Changes apply immediately without restart. The Settings panel describes the option as: "How many scenarios are held in memory for instant switching. Default: 3. Lowering this value may speed up the Suite."