[LEAPSECS] [time-nuts] Leap Quirks
    Rob Seaman 
    seaman at noao.edu
       
    Mon Jan  5 11:09:37 EST 2009
    
    
  
Magnus Danielson wrote:
> Hate to nitpick you, but that is a different representation, not a  
> different interpretation.
Even in technical documentation, words retain their broader meanings.   
I was suggesting that instead of interpreting sexagesimal values as  
sets of integers, one can interpret them as single real values  
(whether fixed or floating point).  One also often interprets  
sexagesimal values as strings.  This may also be a question of  
representation.  And representation is generally an issue for the  
programmer.  Interpretation, an issue for the user.
> The floating point number is thus in hours, is that more practical  
> than say days?
Yes.  A civil clock expresses an angle in h:m:s.  Sexagesimal strings  
broadly represent (or are interpreted as) angles, e.g., latitude,  
longitude, declination, right ascension, galactic latitude and  
longitude, ecliptic latitude and longitude, great circle distances on  
the Earth or the celestial sphere, altitude/elevation and azimuth.   
Whether h:m:s or d:m:s (or decimal representations of hours or degrees  
or radians) these are angles all.
Hence the intuitive conversion between sidereal time and the "hour  
angle" of a telescope.
Rob
    
    
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