Sunlit Design > The Sun API > Documentation > How Time Values are Represented
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How Time Values are Represented
Time values are from one of the following timescales:
- Modified Julian Day (MJD) timescale
- Solar Day of Year (SDY) timescale
- Universal Time Day (UTD) timescale
- Clock Time Day (CTD) timescale
Time values are represented in this program using an XML self describing text format.
The format can be seen clearly from the following examples:
| Timescale | Value | Meaning | Represented as: (String delimiters "") |
| MJD | 51544.0 | Jan 1, 00:00 UT, 2000 | "51544.0 <MJD> 51544.0 </MJD><TimeZone>
0 </TimeZone>" |
| SDY | 20.5 | Jan 20, 12:00 UT | "20.5 <SDY> 20.5 </SDY><TimeZone>
0 </TimeZone>" |
| UTD | 0.25 | 16:00 AEST (Australian Eastern Starnard Time) | ".25 <UTD> .25 </UTD><TimeZone>
-10 </TimeZone>" |
| CTD | 0.75 | 18:00 | ".75 <CTD> .75 </CTD>" |
The sdMJDx, sdSDYx, sdUTDx, sdCTDx, and sdxFindAnnFeatx functions return time values.
The sdxAlt, sdxAzi, sdxDecl, sdxEOT, sdxFindAnnFeatx, sdxH, sdxGetv, sdxTime2Text, and sdxTimeUnpackx functions take time values as parameters.