I am working with overnight data (in particular I am concerned about the hours 6PM-6AM). I want this time frame to count as “day 1” for my study. My problem is that the date changes at midnight. Can anyone recommend code to reassign the time-frames that I am concerned about as “day1, day 2, etc.” instead of the Julian date. I am new to this so any suggestions would be very much appreciated!
*Update, here is a screenshot of the data I am working with. So, the column on the left is the julian date.. in this example I am looking at day 305 and 306 and the hours 18:20 (305) to 6:20 (306). I want these hours to be classified as day 1, instead of the date changing at midnight. Also, I need to get rid of the random date that is attached to my time column. I'm sure there is an easy way to do that, but if anyone knows off the top of your head I'd appreciate that!
Again, I'm very new to R and coding language, please be gentle!
Thanks a million.
You didn't mention what language you're using.
Given timespans 6pm to 6am, I believe the simplest solution would be to decrement 7 hours from any given date - then all of your timestamps would have the start day of the timespan as their day component.
Related
I'm creating a customized function that does some calculations for a given time.
When a time is entered in a cell, for example 4:00 PM, this is automatically converted into a date, in this case 12/30/1899 16:00:00 and when the function getTheMinutes() is called, it returns 2 instead of 0.
function getTheMinutes(dateTime){
return dateTime.getMinutes();
}
The behavior of the function is different if it's used for a most recent date like 5/1/2019 16:00:00.
I want the user to be able to just write a time in a cell then use the customized function in another cell. Please let me know your thoughts.
Now that you have indicated the time zone for your spreadsheet I can confirm what #RobG deduced almost a day ago, which is that Guatemala adjusted its difference relative to UTC. Something you have confirmed is treated as by two minutes with effect from October 5, 1918.
More specifically, the adjustment was of 2 minutes and 4 seconds and effective from 03:00 that day:
(Source IANA Version 2019b file northamerica.)
There have been very many such minor adjustments around the world over the years (even between towns in the same country) and adjustments continue, though usually of a whole hour – between 'standard' and Summer time. Sheets has very properly recognised that "normal arithmetic" 'does not work' across such a transition and while noon yesterday to noon today for example is normally, for any one specific location, a difference of 24 hours it is often 23 hours or 25 hours on the day that clocks go forward/back.
And the moral of the story is to beware of obliging Sheets to assume, for want of a specific date, that is has the index number 0 - i.e. is December 30, 1899.
I made some testing, and I found out that the formula is giving a wrong result any minute before 10/5/1918 0:03:00, from that DateTime on, the formula is working as expected.
Here is my sheet https://docs.google.com/spreadsheets/d/1psm8_GJYRczO53TILJCOzo0p4GpnS-ooiGWqOJrC8ZU/edit?usp=sharing
I would need to do a date validation in my customized formula to make it useful. I don't know why google sheets is choosing that date as default when just a time is typed in a cell, I think it should be improved.
I have a quick question regarding handling of dates and times in 800xA.
What I´m trying to do is to take the current date, add/subtract days and save the result to a new variable.
I´m currently using "Date_and_timetocalendarstruct", to split the current date down to "current year", "current month", "current week" and so on.
I want to work it like this :
for example : take the current date and subtract it by one (or any other number) and thus, generating a new date to store away for future use.
This particular scenario is in ABB,s 800xA systems and its configured against a AC 800M controller.
I have tried a couple of things so for, regarding applying arithmetic operations to dates, but without success.
I hope someone here could point me in the right direction.
Thanks in advance
I think what you missed is the time data type.
date_and_time is used for a Calendar type of Data while time is a time span, e.g. a number of days.
What I understand you want to calculate is (in ST, but works in FBD as well):
OutDate := sub( InDate, Days);
Where OutDate and InDate are of Type date_and_time and Days is time.
If you specify Days with Value 5d, you will get OutDate as 5 days before InDate.
In a similar way, you will get a time span (type time) as output when subtracting two date_and_time values!
I am having trouble grouping certain results in a work in progress report that arranges by start date, I have grouped using fixed values before but because the dates keep moving I am unsure what to do.
The start date is WIP_Schedule.Start_Date
the groups I am trying to create are:
[Group1] Overdue = the current date has passed the start date.
[Group2] (Yet to be named) = the current date 2 week period prior to the start date
[Group3] To Do = the current date after the two week period prior to the start date.
I am after a works instruction on how to achieve this.
I know this isn't a lot of information, if you require any more please ask.
Thanks,
Daniel
This is a pretty straightforward requirement, so you should be able to figure it out by searching the web. However, I'll give you part of the answer and hopefully you can figure it out.
Start by creating a formula to figure out the status of the date.
If {WIP_Schedule.Start_Date} > current date then "Overdue"
Else......
Then you can group based on that formula. All you have to do is figure out the rest of the formula.
I am using Objective-C within X-code.
I am iterating through a dictionary which contains a date value as one of it's keys. All I want to do is get an array of all the distinct dates so I can use them in a table, as headers. I just plan on
iterating the dictionary and adding dates to a mutable array each time I encounter a new date.
I must set previous date to new date for comparisons to work and I am having a very difficult time figuring out how to set one date equal to another date.
This seems like it should be such a simple thing to do and I am trying to avoid converting the dates to strings first - but if that's what I have to do, then so be it.
Any help would be appreciated.
Thanks,
Gerry O.
If you know the time offset is same as GMT, you could do it by dividing the date's timestamp by 86400 seconds (or three more 0s in milliseconds) and comparing those. If a time offset is there, add or subtract by 3600 seconds per hour before you divide them. But then again, leap years and seconds would break that...
Most languages have libraries support extracting the year, date, month, etc. They take everything into account, usually.
In Objc, you can get a NSDateComponents from NSCalendar's components:fromDate: method. After this, you can call the components to see exactly what each component (I suggest year, month, day) is.
I think you want code to compare dates and You need two loops nested.... where in outer loops iterates with conditional inner loop... In inner loop you just check that previously you had the same date or not...
please go through the below post on same site...
How to compare two dates in Objective-C
hope you will get solution... else clarify your question....
I would like to make a function that input a NSDate and output the last date of the month. Do you guys know how to do it in Cocoa?
It's the day before the first day of the next month. Add a month, set the day to 1, subtract a day. For setting the day to 1, you'll find it easier to go via NSCalendar. See here for details.
If you're doing date computations, you should always use NSCalendar and related classes, because that's the only way to be forward-compatible with changes to calendars, support for non-"standard" calendars, and so on.
Read the Date and Time Programming Guide section on Calendrical Calculations to get an idea of how these classes work together.