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RE: st: RE: Date: Thu, 7 Dec 2006 14:48:31 +1100
Naturally, this is the low-level way to attack
each bit of the problem. -ntimeofday- is a tool
that puts it all together to save people from
reinventing each bit of the solution. So, this is
the same answer as mine except that the program
recommended in mine takes care of the details.
Nick
[email protected]
Kyle Hood
> There is a function that allows you to pick out portions of a string
> variable. Because your variable appears to be in a fixed format, you
> might find this function useful. This function is substr():
>
> substr(s,n1,n2) returns the substring of s starting at n1 for
> a length of
> n2. If n1<0, the starting position is interpreted
> distance from the
> end of the string. If n2 is missing (.), the remaining
> portion of the
> string is returned.
>
> Thus, you can pick out the minutes digits, save this in a new
> variable,
> and then destring this variable.
>
> Kyle
>
> On Thu, 7 Dec 2006, Nick Cox wrote:
>
> > There is no way that -destring- can do what you want here,
> > and I speak as its original author still proud of my offspring,
> > despite all that StataCorp programmers have done to it since
> > it left home.
> >
> > -destring- is basically for numbers trapped inside string bodies,
> > such as the string "42" which manifestly would convince all
> > concerned if remodelled as numeric 42. But even shorn of
> all spaces and
> > punctuation, there is no sense in which
> >
> > 2004/01/01 04:05:00
> >
> > would be much use to you reborn as
> >
> > 20040101040500
> >
> > In othr words, -destring- has an -ignore()- option which
> > could be used to get numbers out of your strings, but it is not
> > the answer here. You need code that is smart about seconds, minutes,
> > hours, etc., etc.
> >
> > What you want is reasonable, but what is available to do it
> > consists only of user-written programs. Still, you might
> > -search- for -ntimeofday- and -stimeofday- and try them out.
> >
> > Once you have a date-time expressed in minutes, produce
> > a version that is divided by 5 for -tsset-. You'll need to
> > juggle three versions of the same information, your string
> > for meaning, a date-time number, and something -tsset- will
> > treat as you want.
> >
> > Nick
> > [email protected]
> >
> > Rodrigo Martell
> >
> >> I've loaded some data into Stata. The date variable is a
> >> string and looks like this (yyy/mm/dd hh:mm:ss):
> >> 2004/01/01 04:05:00
> >>
> >> 2004/01/01 04:10:00
> >>
> >> 2004/01/01 04:15:00
> >>
> >> I've been trying to convert the string to Stata dates (and
> >> time) to no avail. I want to eventually -tsset- the
> >> (5-minute) time variable. -destring- won't do because it
> >> doesn't like the / and : (or the spaces I assume) in the date.
> >>
> >> Does anyone have any hints? I'd appreciate it.
>
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