Recent News
SNAP Version 4.1.0 Released
August 19, 2022
AptPlot 8.0.1 Updated
April 29, 2022
PyPost 4.0.2 Released
July 7, 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 4.1.2 - Released 2/16/2023:

  • The email identified in the issue reporting tool has been corrected.
  • An issue has been resolved that would cause closed dialogs to appear in the preview display from the toolbar under Windows.
  • A library update has been added to allow piggy-back plug-ins to support class path entries in their manifest.
  • An issue was resolved where numeric function ordering would not be preserved when the functions were reordered and then model was saved and then loaded.
  • Updated the help button for integration cases to go to the correct part of the user's manual.
  • Numerics Functions have been updated to support manual and automatic execution modes as intended.
  • The comparison method for real values was updated to resolve an issue comparing large negative numbers.
  • The SNAP End User License agreements have changed. See the About Dialog for the new license agreement. The new agreement will be presented during installation. Both the governmental and commercial license agreements can be found in the About dialog.
  • An issue has been resolved which would prevent the issue reporting tool from parsing SNAP installation locations.
  • An issue has been resolved that would prevent executing python job steps under the Windows operating system.
  • An issue was encountered in the SubblockArrayTableDialog which prevents move up/move down when the columns have been deactivated
  • The error message reported when attempting to select a variable reference for a model parameter when there are no variables with equivalent units in the model has been corrected.
  • The update server address has been corrected.
  • The email identified in the issue reporting tool has been corrected.
  • The ModelEditor Welcome dialog was updated to resolve an issue which could cause it to appear at random times where other UI windows may been open.

see older releases