suncal 1.7.0

Sandia PSL Uncertainty Calculator

Uncertainty Calculator

Sandia UNcertainty CALculator (SUNCAL)

Copyright 2019-2025 National Technology & Engineering Solutions of Sandia, LLC (NTESS). Under the terms of Contract DE-NA0003525 with NTESS, the U.S. Government retains certain rights in this software. This software is distributed under the GNU General Public License.

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This tool was developed by the Primary Standards Lab at Sandia National Laboratories to calculate the combined uncertainty of a multi-variable system. Contact [e-mail].

Installation

Installation of the Python package and command line interface requires Python 3.9+ with the following packages:

• numpy
• scipy
• sympy
• matplotlib
• pyqt5
• pyyaml
• markdown
• pint

To install (on Windows, Mac, or Linux), from a command prompt, run:

pip install suncal

Example Usage

From a python terminal, script, or notebook:

import suncal
u = suncal.Model('A*B')
u.var('A').measure(100).typeb(unc=0.1)
u.var('B').measure(2).typeb(unc=0.01)
u.calculate()

See the PDF user's manual and the example notebook files in the docs folder for a complete reference guide.

Command-line script

A script named suncal will be installed to your system path. From a command line, run:

suncal file

where file is the filename of a setup file. See doc/examples folder for example setup files. Refer to the PDF user's manual for other commands.

User interface

A graphical user interface is installed with the Python package. Pre-built executables are available from https://sandiapsl.github.io.

To launch the user interface from a command line, run:

suncalui

or

python -m suncal.gui