[GRASS-dev] granularity function

[Sören Gebbert]

Hi Luca,

2017-05-17 10:51 GMT+02:00 Luca Delucchi <lucadeluge at gmail.com>:
> On 17 May 2017 at 10:08, Sören Gebbert <soerengebbert at googlemail.com> wrote:
>> Hi Luca,
>>
>
> Hi Soeren,
>
>>
>> 2017-05-17 9:36 GMT+02:00 Luca Delucchi <lucadeluge at gmail.com>:
>>> Hi devs, Soeren
>>>
>>> I'm looking for a function that return the number of minutes, days,
>>> months, years according the granularity, for example "2 months" should
>>> return 60 days and "1 years" could return 12 months or 365 days.
>>> does it exist a function like that or could I add it to
>>> lib/python/temporal/temporal_granularity.py ?
>>
>> I am not sure if i understand your approach correctly.
>>
>> IMHO you would like to return the calendar hierarchy of a specific granularity?
>> For example, if the granularity of a STDS is calculated to be 2 month,
>> you would like to return 60 days?
>> This may not be possible, since the number of days in a month vary for
>> each month,
>> as well as the number of days in a year. Hence the result of a
>> granularity computation
>> can not be splittet to a smaller calendar hierarchy, since the term
>> month and year is abstract and not related to a specific year (leap or
>> not) or a specific month (28 - 31 day range).
>>
>> Does this answer your question?
>>
>
> yes and no :-)
>
> you are right that the term month and year is abstract, but we have
> mean values (30 for month and 365 for year) that are commonly
> recognized.
>
> Often colleagues required the mean temperature value for the six
> months before an event, so how to calculate this?

In case of mean values i would prefer the calculated mean of the
Gregorian calendar that is the base of the temporal framework:

1 year = 365.2425 days
1 month =  30.436875 days
6 months = 182.62125
...

Ciao
Sören


>
>> Ciao
>> Sören
>>
>
>
> --
> ciao
> Luca
>
> www.lucadelu.org