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suncycle
PURPOSE ^
SUNCYCLE returns the Time of SunRise, SunSet, Solar Altitude and Radiation
SYNOPSIS ^
function [rs,t,d,z,a,r] = suncycle(lat,lon,date,n)
DESCRIPTION ^
 SUNCYCLE  returns the Time of SunRise, SunSet, Solar Altitude and Radiation

 [SunRiseSet,Day,Dec,Alt,Azm,Rad] = SUNCYCLE( Lat , Lon , Date , N );

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 Inputs:  

   Lat , Lon = geographical Position, scalars

   Date      = [ YYYY MM DD ] or DateNum, multiple Rows allowed
                default: actual Date

   N         = Resolution for Estimation, optional,
                default: 2880 (30 sec Intervall)

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 OutPut: 

  SunRiseSet = [ SunRiseTime  SunSetTime ], decimal hour, refers to GMT
                 special Values: [  0  24 ] Polar Day
                                 [ 24   0 ] Polar Night

  Day        = Decimal Day since [ YYYY 01 01 ], N Columns

  Dec        = Solar Declination,        N Columns
  Alt        = Solar Altitude,           N Columns
  Azm        = Solar Azimuth,            N Columns
  Rad        = Solar Radiation (no-sky), N Columns, [W/mē]
               perpendicular to Earth Surface, i.e. normalized with sin(Alt)
 
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 Solar Radiation outside Athmosphere - Solar Constant: SC = 1370 W/m^2 

 Variation of Solar Radiation due to the ellipticity of the Earth's orbit:

  SC * ( 1 - 0.0335 sin( 2*pi * ( Day - 94 )/365 ) )

 Absorbtion Factor trough Athmosphere via Altitude: 

  Fabs = (1/1.35) .^ ( 1./cos( 2*pi * (90-Alt)/360 ) )
 
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 see also: SUNZENIT, SUNCOVER

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 Code adapted from: AIR_SEA TOOLBOX (version 2.0: 8/9/99)
                    Rich Pawlowicz

 It is put together from expressions taken from Appendix E in the
 1978 edition of Almanac for Computers, Nautical Almanac Office, U.S.
 Naval Observatory. They are reduced accuracy expressions valid for the
 years 1800-2100. Solar declination computed from these expressions is
 accurate to at least 1'.

DOWNLOAD M-File ^
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CROSS-REFERENCE INFORMATION ^
This function calls:
This function is called by:
SUBFUNCTIONS ^
 


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