+1

On Sat, Jun 4, 2016 at 10:22 AM, Charles R Harris <charlesr.harris@gmail.com> wrote:

...

Hi All,

I've made a new post so that we can make an explicit decision. AFAICT, the two proposals are

Integers to negative integer powers raise an error. Integers to integer powers always results in floats.

My own sense is that 1. would be closest to current behavior and using a float exponential when a float is wanted is an explicit way to indicate that desire. OTOH, 2. would be the most convenient default for everyday numerical computation, but I think would more likely break current code. I am going to come down on the side of 1., which I don't think should cause too many problems if we start with a {Future, Deprecation}Warning explaining the workaround.

Chuck

+1 (grudgingly) My thoughts on this are: (i) Intuitive APIs are better, and power(a,b) suggests to a lot of (most?) readers that you are going to invoke a function like the C pow(double x, double y) on every element. Doing positive integer powers with the same function name suggests a correspondence that is in practice not that helpful. With a time machine I’d suggest a separate function for positive integer powers, however... (ii) I think that ship has sailed, and particularly with e.g. a**3 the numpy conventions are backed up by quite a bit of code, probably too much to change without a lot of problems. So I’d go with integer ^ negative integer is an error. Peter