4 Day temperature comparison, including current day
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Mark Clark
le 5 Fév 2019
Modifié(e) : Yair Altman
le 6 Fév 2019
How can I include the current day in the 3 day temperature comparison.
[datetime('today')-days(0),datetime('today')], gives an error
6 commentaires
Guillaume
le 5 Fév 2019
Is that the full text of the error message. Usually it also states which line(s) is responsible for the error. This is essential information we need, particularly since I cannot see anywhere in your code where you use [datetime('today')-days(0),datetime('today')].
On the other hand the error message is clear. The two dates you pass must be different, with the second one later than the first. Of course, subtracting 0 days from a date doesn't change that data, so [datetime('today')-days(0),datetime('today')] is twice the same date.
It's unclear what you expected to do with that.
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Omer Yasin Birey
le 5 Fév 2019
Modifié(e) : Omer Yasin Birey
le 5 Fév 2019
You can try to use the last minute of the current day, since it says starting date must be before than ending date
todayDate = datetime('today');
todayDate = todayDate + minutes(1439);
[datetime('today')-days(0),todayDate]
4 commentaires
Guillaume
le 6 Fév 2019
Well ok, it does create a datetime with a different display format. If that's the whole purpose of subtracting 0, then I would say it's a bad idea. First, you're relying on undocumented behaviour, so that may change in a future release without notice. Secondly, if you want a specific format you'd be better be explicit about the format you want. So even though, 'Format', 'dd, MMM, yyyy HH:mm:ss' might be longer, it's at least very clear what the intent of the code is. Subtracting 0 just to alter the format, with no comment explaining what the purpose is, is just asking for a bug to be introduced later on when a different maintainer notice that 0 subtraction and remove it.
In this particular case, where the array is just passed to another function, the format does not matter at all.
Yair Altman
le 6 Fév 2019
Modifié(e) : Yair Altman
le 6 Fév 2019
I echo Guillaume's comment.
However, just for the record, it is typically faster to subtract a pure number rather than days(number). For example,
datetime('today')-1
is faster than
datetime('today')-days(1)
and yet has the same meaning/result. Just note that days(1) might be more readable.
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