On Wed, 30 Apr 2008, John Maddock wrote:
dherring@ll.mit.edu wrote:
On Tue, 29 Apr 2008, John Maddock wrote:
Folks I'm looking for some good names for some functions I'm on the brink of adding to Boost.Math (all in namespace boost::math::):
T nextafter(T val, T dir) T next_greater(T val) T next_less(T val)
Given the first name is fixed, this is a reasonable family of names; though dropping the underscore would increase consistency. However, there is the ambiguity whether greater/less reference zero or infinity.
Not sure what you mean there, next_greater returns a value that is strictly greater than the argument (so always moves towards positive infinity).
I confused myself. Standard terminology says < and > are "less than" and "greater than"; so your names are fine. Still think the underscore should be dropped for consistency.
float x=1.0; float y=2.0; int d=edit_distance(x, y); float z=x; for(int i=0; i<d/2; i++) { z=next_greater(z); } // Does y==(x+z)/2, given the right rounding mode?
Change i<d/2 to i<2*d and yes I believe so.
That was supposed to read // Does z==(x+y)/2? Which I think you've answered as yes. All of these operations apply to integers (albeit in the trivial sense that i and i+1 are always separated by a single gap). Thus it might be nice if these operators could be applied to all numeric types, integers and floating-point. Thanks, Daniel