Re: Eye Reasoner Builtin/N3 question/challenge

Corrections below:

On Mon, Oct 3, 2022 at 12:43 PM tim duval <tim.duval11@gmail.com> wrote:

> Thanks Jos! I will definitely check out the time samples
>
> *Regarding regular expressions:*
> I find that string:matches() returns a boolean whether or not the string
> matches the regular expression,
> I am looking to extract the number from the string based on the regular
> expression.
> For example, I would like to assign the result of re.match('13.4 kV',
> '\d+\\.*\\d*') to a variable, the result being 13.4
>
> *Regarding coalesce:*
> Coalesce returns the first non-null value from a list/collection.
>


> I believe there is no concept of null in rdf, I see that *rdf:nil*
> available to represent NULL, so I am thinking this would be translated into
> returning the first item from a list/collection that is not empty rdf:nil
> (i'm checking R2RML spec to see how nulls are handled when converting dbms
> to rdf)
>
> https://www.ibm.com/docs/en/informix-servers/14.10?topic=expressions-coalesce-function
>
>
> On Mon, Oct 3, 2022 at 11:11 AM Jos De Roo <josderoo@gmail.com> wrote:
>
>> Indeed and for reasoning with time we have https://www.w3.org/TR/rif-dtb/
>> implemented in eye see
>> https://github.com/josd/eye/blob/master/reasoning/rif/rifP.n3
>>
>> dunno what coalesce is, maybe something like in
>>
>> https://github.com/phochste/Notation3-By-Example/blob/main/string/concatenation.n3
>> ?
>>
>> Jos
>>
>> -- https://josd.github.io
>>
>>
>> On Mon, Oct 3, 2022 at 5:02 PM tim duval <tim.duval11@gmail.com> wrote:
>>
>>> I found that string:matches() looks like it can satisfy handling regular
>>> expressions
>>>
>>> Just the other two that I could use some help.
>>>
>>>
>>>
>>> On Mon, Oct 3, 2022 at 10:24 AM, tim duval <tim.duval11@gmail.com>
>>> wrote:
>>>
>>>> Hi!
>>>>
>>>> We are on the verge of implementing N3 for a product I am helping a
>>>> client develop and in their due diligence, they are providing me with
>>>> challenges to identify what the N3 equivalent is, e.g., Let's see if N3 can
>>>> handle this!! (suffice to say there is a little skepticism)....
>>>>
>>>> Most of the list is easy to handle, though a few of them stuck out to
>>>> me that it would be best to ask the community how these might be
>>>> represented in N3 (built-in wise):
>>>>
>>>> *Coalesce:*
>>>> Coalesce(@StatusCode,'123')
>>>>
>>>> *Regex expressions:*
>>>> how can regular expressions be used??
>>>> e.g., substring('13.4 kv', '(([0-9]+.*)*[0-9]+)') as decimal -->
>>>> returns 13.4
>>>>
>>>> *Convert time to current/provided timezone:*
>>>>
>>>> session-created-date-utc = "2022-08-15 18:57:40"
>>>>
>>>> current-timezone = 'CDT'
>>>>
>>>> result is:  "2022-08-15 12:57:40"
>>>>
>>>>
>>>> Any help is appreciated
>>>>
>>>>
>>>> Thanks!
>>>>
>>>>
>>>> Tim Duval
>>>>
>>>>
>>>>