Molecular modelers often face the challenge of navigating complex systems where groups of nodes, each with specific attributes, need to be selected or identified for further analysis or modeling tasks. SAMSON’s Node Specification Language (NSL) addresses this pain point by offering intuitive attribute spaces, and one particularly useful feature is the nodeGroup attribute space.
The nodeGroup attribute space, abbreviated as ng, is tailored specifically for interacting with node group nodes. This feature allows you to streamline tedious node management tasks, such as naming, selecting, and working with selection flags. In this blog post, we’ll take a closer look at its key attributes (name, selected, and selectionFlag), providing some concrete examples of how you can use them to simplify your workflows.
Key Attributes in the nodeGroup Attribute Space
1. name
The name attribute is used to identify node groups with a specific string. For example, if you want to select node groups with a name like “A” or starting with “L”, you’ll use expressions like:
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ng.n "A" ng.n "L*" |
This is particularly handy for working with named regions or groups in your models, as it allows you to find and act on them more efficiently.
2. selected
The selected attribute enables you to check whether a node group is selected. Since it doesn’t have a short name in this context, an example usage might look like this:
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ng.selected not ng.selected |
This is useful during analysis when you need to isolate specific node groups or exclude those that are already selected.
3. selectionFlag
The selectionFlag, abbreviated as sf, helps indicate whether a particular node group has a selection flag. For instance, setting the selection flag to false for a node group can be done via:
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ng.sf false |
You can also directly access node groups with a selection flag:
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ng.sf |
As a molecular modeler, this simplifies tasks like tracking and filtering groups during iterative workflows.
Why Mastering nodeGroup Attributes Matters
Understanding and leveraging the nodeGroup attribute space in NSL empowers you to fine-tune your modeling processes. Whether assigning specific attributes to a group of atoms, highlighting regions of interest, or ensuring consistency across node groups, these attributes serve as practical tools to save time and minimize errors.
If you’re new to using the nodeGroup attribute space, we recommend experimenting with basic expressions like those highlighted above. This hands-on approach offers a deeper understanding of how NSL can align with your specific modeling needs.
For further details and additional examples, be sure to visit the official documentation page on node group attributes.
Note: SAMSON and all SAMSON Extensions are free for non-commercial use. To access these features and explore SAMSON’s full potential, download SAMSON here.