ANN: intervalset Was: Set type for datetime intervals

[Oscar Benjamin]

On 4 April 2016 at 16:09, Random832 <random832 at fastmail.com> wrote:
> On Mon, Apr 4, 2016, at 03:12, Nagy László Zsolt wrote:
>>
>>   Hi All,
>>
>> If anyone is interested, a module was born:
>>
>> https://bitbucket.org/nagylzs/intervalset
>> https://pypi.python.org/pypi/intervalset/0.1.1
>
> I don't know if I like it being immutable. Maybe have separate mutable
> and immutable versions.
>
> Like I said before, I don't think the set-like operations on Intervals
> are useful - what can you accomplish with them rather than by making a
> set consisting of only one interval and doing operations on that?

I guess it depends what your application is but sympy has interval
sets and can do computation on them to represent the solutions of
equations/inequalities (many other types of set are also included).
For example:

In [1]: from sympy import Interval

In [2]: Interval
Out[2]: sympy.core.sets.Interval

In [3]: Interval(1, 2)
Out[3]: [1, 2]

In [4]: help(Interval)


In [5]: Interval(1, 2) & Interval(3, 4)
Out[5]: ∅

In [6]: Interval(1, 2) | Interval(3, 4)
Out[6]: [1, 2] ∪ [3, 4]

There is some discussion about why it's good to do this stuff with
sets (for sympy's purposes here):
http://docs.sympy.org/latest/modules/solvers/solveset.html#why-do-we-use-sets-as-an-output-type

--
Oscar