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Re: Time convertion





JD Smith wrote:
...  In any case,
> it is oh so trivial to convert date to systime, the inverse:
> 
> st=(julday(month,day,year,hr,min,sec)-2440587.5D)*86400.0D
> 
> That's it!  For instance:
> 
> IDL> st0=systime(0) & st1=systime(1)
> IDL> d=bin_date(st0)
> IDL> st=(julday(d[1],d[2],d[0],d[3],d[4],d[5])-2440587.5D)*86400.0D
> IDL> print,FORMAT='(A,":",2D30.5)',st0,st1,st
> 
...
> 
> JD

How are leap seconds accounted for here?  They usually cause
niggling problems if one actually needs to worry about
precision at the second level over periods of more than a
month or two.  It looks like your code is ignoring them.
The biggest pain is that they are not predictable so the
code needs to access an external file, or update an
internal table periodically.

	Regards,
	Tom McGlynn