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From: fred bertsch (fred.bertsch_at_[hidden])
Date: 2006-05-31 13:34:03

The review of Andy Little's Physical Quantities System begins today,
May 31, 2006, and continues through June 9, 2006.


pqs_3_1_0 is the Official Boost Review version of pqs. (Please note
that pqs_3_1_0 has a bug in one header. This can be either patched
according to the latest release notes, "relnotes.txt" available from or alternatively download pqs_3_1_1, which is
basically equivalent to pqs_3_1_0, except the bug has been fixed


PQS (Physical Quantities System) is designed to replace the use of
floating point types for modelling physical quantities in C++
programs. Advantages include automated dimensional analysis checking,
automatic unit conversions, self documentation of code and uniform
mechanisms for dealing with physical quantities overall, allowing
better interoperability, accuracy and repeatability among engineering,
physics and trade applications.

The library will ultimately consist of various types for modelling
quantities in different situations. The t1_quantity, which is the
first to be implemented, performs all its dimensional analysis checks
as well as parts of its unit conversion calculations, at compile time
rather than runtime, for maximum efficiency.

PQS is designed with a firm commitment to the SI system, as being the
internationally agreed preferred system of units. A reasonable
selection of common quantities and units is included in the review
version for demonstration purposes. The intent is to expand on this to
include all the common quantities mentioned in Appendix B.8 and B.9 of
the NIST SI document:

The library also defines a selection of physical constants again
intended as a flavour of the constants that would be included in a
full library implementation as outlined in:

Review questions:

Please always explicitly state in your review, whether you think the
library should be accepted into Boost.

You might want to comment on the following questions:

 - What is your evaluation of the design?
 - What is your evaluation of the implementation?
 - What is your evaluation of the documentation?
 - What is your evaluation of the potential usefulness of the library?
 - Did you try to use the library? With what compiler? Did you have
any problems?
 - How much effort did you put into your evaluation? A glance? A quick
reading? In-depth study?
 - Are you knowledgeable about the problem domain?

-Fred Bertsch

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