Recent News
SNAP Version 4.2.0 Released
November 3, 2023
AptPlot 8.0.3 Updated
May 22, 2023
PyPost 4.0.3 Released
August 18, 2022

Symbolic Nuclear Analysis Package

The Symbolic Nuclear Analysis Package (SNAP) consists of a suite of integrated applications designed to simplify the process of performing engineering analysis. SNAP is built on the Common Application Framework for Engineering Analysis (CAFEAN) which provides a highly flexible framework for creating and editing input for engineering analysis codes as well as extensive functionality for submitting, monitoring, and interacting with the codes.

Important Notice Concerning Log4J Vulnerability (CVE-2021-44228): The Log4j utility is included in earlier versions of AptPlot and SNAP. We recommend that you promptly delete any earlier versions of AptPlot or SNAP that you may have installed and update to the latest version of this software. AptPlot Version 8.0 which is now included as a plug-in to SNAP Version 4.0.1 was released in October 2021.  These versions of AptPlot and SNAP do not include the Log4J utility. 

Download SNAP

Getting Started

A guide to downloading and installing SNAP and its prerequisite software.


Users' manuals, on-line instruction, tutorials, and other SNAP related materials.

SNAP Plug-ins

Find information about the various SNAP plug-ins available to users.

Technical Support

Technical support is available to CAMP members, NRC contractors and SNAP User's Group members.

Change Log

SNAP 4.2.0 - Released 11/03/2023:

  • Unitless model properties that reference SNAP variables with different engineering units will correctly handle the differing conversion factors for internal comparison in British models.
  • The restore session dialog has been updated to provide a more stable launch process.
  • The real and integer numeric execution logic was optimized to no longer perform double execution when a value is set.
  • The Model Editor initialization logic was updated to add further stability to the application.
  • The ability to export and import Numeric Tables using Microsoft Excel formatted files has been added.
  • The ability to export and import Numeric Tables using Numerics Import Format formatted files has been added.
  • The ability to export and import Python Functions using Numerics Import Format formatted files has been added.
  • A line counter has been added to the Python Source editing dialog when the function is using Jython for execution.
  • An error will be shown when the line count of a Jython function is too high.
  • A comparator has been implemented into ComponentSelectionDialog to handle numerics within the component list.
  • Python functions have been updated to allow plug-ins to enable Python binding access inside Python functions.
  • An issue was resolved in which an error would be reported during import of a table from an NIF file.
  • When exporting tables and functions to an NIF file they are exported in the top of the file in the order in which they appear in the navigator.

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