On 7 Oct 2011, at 22:22, Murray Sargent wrote: > In the linear format of UTN #28, 1/2/3/4 builds up as ((1/2)/3)/4 as in > computer languages like C.
OK. I looked through the paper again, and could not find a description of that. > The notation actually started with C semantics and then added a larger set of > operators, and finally adopted the full Unicode set of mathematical operators. In view of the problems of C semantics, as C++ shows, I am actually reviewing it. > You can try it out in Microsoft Office applications. I do not have access to that. > Different groupings can be obtained by using parentheses, which may be > discarded after build up as explained in UTN #28. As Asmus points out, I > started working on this notation back in the late 1970's and the latest > version is built into a number of popular products. So it's pretty thoroughly > tested. I am worrying also about the underlying mathematical semantics, where one can have different models. One is having the set if integers ℤ different from the set of rational ℚ numbers (as in C/C++), or viewing it as embedded (as in Scheme). In math, one shifts between the two according to context. The ideal would be to avoid implicit type conversions, but that would not work if one would want to be able to be able to enter numbers in common form. Hans
