Selecting the right atoms or other nodes can become surprisingly fiddly. A viewport click may pick the wrong kind of object, a long molecular hierarchy can be hard to scan, and a selection that looks right may still include too much. A practical solution is to treat selection as a short workflow: choose the right selection route, narrow the candidates, check the result, and save it if you will need it again.
Choose where to select
In SAMSON, you can select nodes in either the viewport or the Document view. These are useful for different situations. The viewport is convenient when the target is easy to identify visually. The Document view is often more helpful when you know the node’s place in the document hierarchy or want to filter nodes by name or a Node Specification Language (NSL) expression.
In the viewport, activate a selection editor and use the selection filter in the top-right corner to control which node types can be highlighted and selected. This is a useful first check when clicking keeps selecting an unintended type of node: adjust the filter before trying again.
Narrow a selection in the Document view
Click a node in the Document view to select it and highlight it in the viewport. For a multi-selection, use Shift and Ctrl on Windows or Linux, or Shift and Cmd on macOS. If the hierarchy is large, use the Document view filter instead of repeatedly scrolling. Enter text or an NSL expression, then press Enter to select the matching nodes.
This gives you two complementary approaches: use text when you know what to look for, and use an NSL expression when you want to describe the nodes to select. For example, filtering can help when the relevant nodes are difficult to distinguish in a crowded 3D view. The selection still appears in the viewport, so you can check that the result corresponds to the intended part of the structure.
Use Find for an expression-based selection
When it is more natural to specify a selection directly, use Select > Find. The shortcut is Ctrl+F on Windows or Linux, or Cmd+F on macOS. Find uses the Node Specification Language to select matching nodes. This can be a more controlled alternative to picking objects one by one, particularly when the target is defined by node properties rather than by its visible position.
Whatever route you use, make a quick verification part of the process. The bottom of the Document view shows a summary of the current selection. Click the summary to open contextual actions for that selection. Checking the summary before moving, editing, or applying a tool helps catch an overly broad or incomplete selection early.
Keep a useful selection
If you expect to return to the same set of nodes, save the current selection as a node group with Select > Group, or press G. The group records the selection in the document. Double-click the group in the Document view to restore that selection later. This is especially handy when you are switching between parts of a document and want to avoid rebuilding a selection from scratch.
A simple routine makes selection less error-prone: use the viewport for visually obvious targets, use the Document view or Find when filtering is clearer, inspect the selection summary, and group selections you will reuse. For details on selection editors and other selection methods, see the Selecting guide. For the broader workflow and other first steps, see the SAMSON Quick Start Guide.
Note: SAMSON and all SAMSON Extensions are free for non-commercial use. Get SAMSON.