
Key: EXPRESS6

Legacy Issue Number: 14071

Status: closed

Source: THALES ( Hugues Vincent)

Summary:
Clause 9.8.2 I don't know what the "Napierian exponential function" is. Perhaps it is more usual to native English speaker? Yet I didn't find anything worthwhile when I googlized it (is Google anyway a reference?). I just know the "exponential function" and the "naperian logarithm function" which is the inverse of the preceding.
Yet defining e from one of these functions whose definitions are, AFAIK, based on e itself doesn't make sense.
I'd recommand to use the original Euler's definition: see http://en.wikipedia.org/wiki/E_(mathematical_constant)#History
If agreed, that could be handled through an issue for the 2nd FTF. 
Reported: EXPRESS 1.0b1 — Tue, 23 Jun 2009 04:00 GMT

Disposition: Resolved — EXPRESS 1.0b2

Disposition Summary:
The definition of E in the specification was taken verbatim from ISO 1030311 Clause 14.2. However, the issue is correct: Napier published a table of natural logarithms, but the exponential function is credited to Euler. The specification should use one of Euler's definition (based on the area under the curve 1/x), or Bernoulli's definition (the limit of (1+1/n)n).

Updated: Fri, 6 Mar 2015 20:58 GMT
EXPRESS — EXPRESS MM issue: Correct definition of E
 Key: EXPRESS6
 OMG Task Force: EXPRESS Metamodel FTF