
NPL's GUM Supplement 1 Published Software
-----------------------------------------

This file describes the files that constitute Release 1.1 of NPL's 
GUM Supplement 1 Published Software (also known as NPL's NPLUnc_101
Open-Source Software).

The software was developed at the National Physical Laboratory, UK,
to support the use of the Guide to the expression of uncertainty in 
measurement (GUM) and the first supporting document to the GUM, 
GUM Supplement 1, concerned with the use of a Monte Carlo method as 
an implementation of the propagation of distributions.

The software, developed in the MATLAB programming language, is provided 
in the form of M-files in the folder 'source', and in the folder 'html' 
as HTML files published using MATLAB Version 7.11.0 (R2010b). 

For users of MATLAB, the M-files may be run directly, and also modified 
to run the software for different measurement problems. 

The main M-file is NPLUnc_101_source.m. The M-files GUM_calculation.m and 
MCM_calculation.m contain functions implementing, respectively, the GUM 
uncertainty framework and a Monte Carlo method for uncertainty evaluation. 
The M-file GUM_validation.m contains functions for displaying and comparing 
the results obtained from the two methods. Finally, the M-file model_additive.m 
contains an example of a function implementing a measurement model. The 
example considered is the additive model

	Y = X_1 + X_2 + ... + X_N.

For users who do not have access to MATLAB, the software is best viewed as 
the provided HTML files. To do this, the user can, for example, move to the 
folder containing the HTML files and open the main file NPLUnc_101_source.html
using a browser such as Microsoft Internet Explorer. 

The file NPLUnc_101_source.html contains links to the other HTML files as well 
as to the following documents:

ms7.pdf: a specification of software implementing the GUM uncertainty 
	framework and a Monte Carlo method;

NPLUnc_101_MSC_L_15_011.pdf: a software user licence agreement (see 
	below);

GUMS1Software-UM_R11.pdf: a report containing documentation for NPL's
	GUM Supplement 1 software.

The software is provided with extensive commenting to help practitioners 
develop their own implementations of the software, which may be in other 
programming languages and for other software systems. Some use of MATLAB 
intrinsic functions is made and implementations of such functions would 
also need to be developed.

The software is provided with a software user licence agreement 
(MSC/L/15/011) and the use of the software is subject to the terms laid 
out in that agreement. By running the M-code, the user accepts the terms 
of the agreement. 

The software should be used in conjuction with the GUM, GUM Supplement 1, 
the report GUMS1Software-UM_R11.pdf, and the specification ms7.pdf of 
software implementing the GUM uncertainty framework and a Monte Carlo 
method. 

Enquiries about the software should be directed to 

Ian Smith (ian.smith@npl.co.uk) 

or

Peter Harris (peter.harris@npl.co.uk). 


