[R] Question on creating Date variable

[Christofer Bogaso]

On 01 January 2013 01:29:53, David Winsemius wrote:
>
> On Dec 31, 2012, at 11:35 AM, Christofer Bogaso wrote:
>
>> On 01 January 2013 00:17:50, David Winsemius wrote:
>>>
>>> On Dec 31, 2012, at 9:12 AM, Christofer Bogaso wrote:
>>>
>>>> Hello all,
>>>>
>>>> Let say I have following (numeric) vector:
>>>>
>>>> > x
>>>> [1] 11.00 11.25 11.35 12.01 11.14 13.00 13.25 13.35 14.01 13.14 14.50
>>>> 14.75 14.85 15.51 14.64
>>>>
>>>> Now, I want to create a 'Date' variable (i.e. I should be able to do
>>>> all calculations pertaining to date/time and also time-series
>>>> plotting etc.) like
>>>>
>>>> 2012-12-31 11:00:00 AM, 2012-12-31 11:25:00 AM, 2012-12-31 11:35:00
>>>> AM, 2012-12-31 12:01:00 PM, . . . .
>>>>
>>>
>>> Those _times_ ( _not_ Dates) cannot possibly be in %M.%S" format,
>>> given the number of items to the right of the decimal point that are
>>> greater than 60. So will proceed on the arguably more likely
>>> assumption that they are in fractional minutes. To recover from that
>>> problem, one might consider:
>>>
>>> > as.POSIXct(paste( floor(x), round(60*(x-floor(x))) ), format="%M %S")
>>> [1] "2012-12-31 00:11:00 PST" "2012-12-31 00:11:15 PST"
>>> [3] "2012-12-31 00:11:21 PST" "2012-12-31 00:12:01 PST"
>>> [5] "2012-12-31 00:11:08 PST" "2012-12-31 00:13:00 PST"
>>> [7] "2012-12-31 00:13:15 PST" "2012-12-31 00:13:21 PST"
>>> [9] "2012-12-31 00:14:01 PST" "2012-12-31 00:13:08 PST"
>>> [11] "2012-12-31 00:14:30 PST" "2012-12-31 00:14:45 PST"
>>> [13] "2012-12-31 00:14:51 PST" "2012-12-31 00:15:31 PST"
>>> [15] "2012-12-31 00:14:38 PST"
>>>
>>
>> I understand that some of those elements are not "dates". However
>> what I want is the ***"PM/AM" suffix*** on those elements which are
>> considered as Dates.
>>
>> ***Getting those suffix*** and doing calculations on those changed
>> variables is my primary concern.
>
> That's the first time that AM/PM has bee mentioned and I suppose if
> those were fractional hours rather than my guess of fractional minutes
> that there might be representatives of both in the numeric data you
> offered. Why don't you clarify what these number do in fact represent?
> And what problem you are trying to solve?
>

Basically those are artificial data! Actually I do not have the right 
to give out the original data in any public forum. So I created those 
artificial data so that I can get the fundamental idea ...........

Each element (assuming they are legitimate time) represents the time 
for a particular day when some event is pop-up. like, 11AM, 11.30AM, 
12.05PM etc.. I could work with something like 11.00, 11.30, 12.05, 
15.00 etc. however I believe adding AM/PM suffice will make my report 
more eye-catching.

Please let me know if you need more clarification.

Thanks and regards,