Looking at the source for simpnrt, I think both of its arguments should be integers, but sometimes
simpnrt is called with noninteger arguments: for example, integrate(exp((-1+%i)*x^2),x,minf,inf).
Calling simpnrt directly instead of using the services of simpexpt might save time, but it is risky.
It's pure speculation, but some direct calls to simpnrt might be there to cover up bugs that would
manifest if the expression were sent all the way through simpexpt.
Another example of a call to simpnrt with noninteger arguments:
(%i8) integrate(exp(-(12 +%i)^2*x^2),x,minf,inf);
taylor: assumed to be zero: %e^(-143*x^2)
taylor: assumed to be zero: %e^(-143*x^2)
taylor: assumed to be zero: %e^(-143*x^2)
(%o8) (12*sqrt(%pi))/145-(sqrt(%pi)*%i)/145
Ugh! I think the answer is correct, but why does taylor get called for such a simple calculation?
--Barton