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Last modified: Tue Jul 11 20:43:20 2006.
NAME:
decstrf
PURPOSE: (one line)
Convert declination in radians to an ASCII string.
DESCRIPTION:
CATEGORY:
Astronomy
CALLING SEQUENCE:
str = decstrf(dec, places)
INPUTS:
dec - Declination, in radians, to be converted to a string. May
a vector, in which case the output will be a vector.
OPTIONAL INPUT PARAMETERS:
places - Resolution of output string (integer).
= -7 nearest hour. +DD
= -6 nearest 30 minutes. +DD:(00,30)
= -5 nearest 15 minutes. +DD:(00,15,30,45)
= -4 nearest 10 minutes. +DD:M0
= -3 nearest 5 minutes. +DD:M(0,5)
= -2 nearest minute. +DD:MM
= -1 nearest ten seconds. +DD:MM:S0
= 0 nearest second. +DD:MM:SS
= 1 nearest tenth of a second. +DD:MM:SS.s
= 2 nearest hundredth of a second. +DD:MM:SS.ss
= 3 nearest thousandth of a second. +DD:MM:SS.sss
KEYWORD INPUT PARAMETERS:
none
KEYWORD OUTPUT PARAMETERS:
none
OUTPUTS:
str - Output string for the converted dec
COMMON BLOCKS:
SIDE EFFECTS:
RESTRICTIONS:
PROCEDURE:
Call the PROCEDURE decstr
MODIFICATION HISTORY:
Written 2006 Feb 27, by Leslie Young, SwRI
(See astronomy/decstrf.pro)
NAME:
elems
PURPOSE: (one line)
Return orbital elements to pass to ephem
DESCRIPTION:
Return orbital elements to pass to ephem
CATEGORY:
Astronomy
CALLING SEQUENCE:
e = elems(p)
INPUTS:
p - planet number. 1 = mercury, etc.
OPTIONAL INPUT PARAMETERS:
none
KEYWORD INPUT PARAMETERS:
none
KEYWORD OUTPUT PARAMETERS:
none
OUTPUTS:
elem - vector of 7 elements
e Eccentricity (degrees)
i Inclination w.r.t xy-plane (degrees)
LAN Longitude of Ascending Node (degrees)
APF Argument of Perifocus (degrees)
tau Julian Date of last periapsis
n Mean motion (au/day)
A semimajor axis.
COMMON BLOCKS:
None
SIDE EFFECTS:
RESTRICTIONS:
None
PROCEDURE:
MODIFICATION HISTORY:
Written 2000, by Leslie Young, SwRI
(See astronomy/elems2007.pro)
NAME:
ephem
PURPOSE: (one line)
Return heliocentric position and velocity
DESCRIPTION:
Given t in Julian date and orbital elements, return heliocentric XYZ in AU, and, optionally,
velocity in AU/day
CATEGORY:
Astronomy
CALLING SEQUENCE:
xyz = ephem(elem, t, uvw)
INPUTS:
elem - vector of 6 or 7 elements
e Eccentricity (degrees)
i Inclination w.r.t xy-plane (degrees)
LAN Longitude of Ascending Node (degrees)
APF Argument of Perifocus (degrees)
tau Julian Date of last periapsis
n Mean motion (au/day)
A semimajor axis. If not passed, assume M = solar
t - Julian date
OPTIONAL INPUT PARAMETERS:
none
KEYWORD INPUT PARAMETERS:
none
KEYWORD OUTPUT PARAMETERS:
none
OUTPUTS:
xyz - vector of position in AU
uvw - vector of velocity in AU/day
COMMON BLOCKS:
None
SIDE EFFECTS:
RESTRICTIONS:
None
PROCEDURE:
MODIFICATION HISTORY:
Written 2000, by Leslie Young, SwRI
(See astronomy/ephem.pro)
NAME:
ephemLAY
PURPOSE: (one line)
Return heliocentric position and velocity
DESCRIPTION:
Given t in Julian date and orbital elements, return heliocentric XYZ in AU, and, optionally,
velocity in AU/day
CATEGORY:
Astronomy
CALLING SEQUENCE:
xyz = ephemLAY(elem, t, uvw)
INPUTS:
elem - vector of 6 or 7 elements
e Eccentricity (degrees)
i Inclination w.r.t xy-plane (degrees)
LAN Longitude of Ascending Node (degrees)
APF Argument of Perifocus (degrees)
tau Julian Date of last periapsis
n Mean motion (deg/day)
A semimajor axis. If not passed, assume M = solar
t - Julian date
OPTIONAL INPUT PARAMETERS:
none
KEYWORD INPUT PARAMETERS:
none
KEYWORD OUTPUT PARAMETERS:
none
OUTPUTS:
xyz - vector of position in AU
uvw - vector of velocity in AU/day
COMMON BLOCKS:
None
SIDE EFFECTS:
RESTRICTIONS:
None
PROCEDURE:
MODIFICATION HISTORY:
Written 2000, by Leslie Young, SwRI
2005 Oct 17 LAY changed documentation for n (was au/day)
(See astronomy/ephemLAY.pro)
NAME: geocllh2xyz PURPOSE: (one line) Convert geocentric latitude, longitude, and height to cartesian coordinates DESCRIPTION: Convert geocentric latitude, longitude, and height to cartesian coordinates CATEGORY: Astronomy CALLING SEQUENCE: geocllh, lat, long, h, x, y, z INPUTS: OPTIONAL INPUT PARAMETERS: none KEYWORD INPUT PARAMETERS: none KEYWORD OUTPUT PARAMETERS: none OUTPUTS: Planck function COMMON BLOCKS: uses share_physconst SIDE EFFECTS: RESTRICTIONS: Must run phys_const first For now, T and nu are scalars Doesn't check if h nu/k T << 1 PROCEDURE: MODIFICATION HISTORY: Written 2000 April, by Leslie Young, SwRI
(See astronomy/geocllh2xyz.pro)
NAME:
latstr
PURPOSE: (one line)
Convert latitude in radians to an ASCII string.
DESCRIPTION:
CATEGORY:
Astronomy
CALLING SEQUENCE:
latstr, latitude, places, str
INPUTS:
latitude - Latitude, in radians, to be converted to a string. May
a vector, in which case the output will be a vector.
places - Resolution of output string.
= -7 nearest hour. +DD
= -6 nearest 30 minutes. +DD:(00,30)
= -5 nearest 15 minutes. +DD:(00,15,30,45)
= -4 nearest 10 minutes. +DD:M0
= -3 nearest 5 minutes. +DD:M(0,5)
= -2 nearest minute. +DD:MM
= -1 nearest ten seconds. +DD:MM:S0
= 0 nearest second. +DD:MM:SS
= 1 nearest tenth of a second. +DD:MM:SS.s
= 2 nearest hundredth of a second. +DD:MM:SS.ss
= 3 nearest thousandth of a second. +DD:MM:SS.sss
OPTIONAL INPUT PARAMETERS:
KEYWORD PARAMETERS:
SEPCHAR - Separator character for the fields in the position.
Default=':'. Warning, if you do not use ':' then the
string may not be parsable by raparse.
FORMAT = 'E' for east latitude, 'W' for west long. Default = positive.
OUTPUTS:
str - Output string for the converted latitude.
COMMON BLOCKS:
SIDE EFFECTS:
RESTRICTIONS:
PROCEDURE:
East latitude (in the range [-pi,pi]) is converted to a string.
The sign of the latitude is always provided and there are no imbedded
blanks. PLACES indicates the reported precision of the string.
Calls external routine radtodms.
MODIFICATION HISTORY:
Copyright (C) 1987,91, by Marc W. Buie
Version dated 91/8/5
Ported by Doug Loucks, Lowell Observatory, August 11, 1993, from the
C-Language version written by Marc Buie.
2003/05/09, MWB, added SEPCHAR keyword
(See astronomy/latstr.pro)
NAME:
latstrf
PURPOSE: (one line)
Convert latitude in radians to an ASCII string.
DESCRIPTION:
CATEGORY:
Astronomy
CALLING SEQUENCE:
str = latstrf(lat, places)
INPUTS:
lat - Latitude, in radians, to be converted to a string. May
a vector, in which case the output will be a vector.
OPTIONAL INPUT PARAMETERS:
places - Resolution of output string (integer).
= -7 nearest hour. +DD
= -6 nearest 30 minutes. +DD:(00,30)
= -5 nearest 15 minutes. +DD:(00,15,30,45)
= -4 nearest 10 minutes. +DD:M0
= -3 nearest 5 minutes. +DD:M(0,5)
= -2 nearest minute. +DD:MM
= -1 nearest ten seconds. +DD:MM:S0
= 0 nearest second. +DD:MM:SS
= 1 nearest tenth of a second. +DD:MM:SS.s
= 2 nearest hundredth of a second. +DD:MM:SS.ss
= 3 nearest thousandth of a second. +DD:MM:SS.sss
KEYWORD INPUT PARAMETERS:
SEPCHAR - Separator character for the fields in the position.
Default=':'. Warning, if you do not use ':' then
the
string may not be parsable by raparse.
KEYWORD OUTPUT PARAMETERS:
none
OUTPUTS:
str - Output string for the converted lat
COMMON BLOCKS:
SIDE EFFECTS:
RESTRICTIONS:
PROCEDURE:
Call the PROCEDURE latstr
MODIFICATION HISTORY:
Written 2006 Feb 27, by Leslie Young, SwRI
(See astronomy/latstrf.pro)
NAME:
lonstr
PURPOSE: (one line)
Convert longitude in radians to an ASCII string.
DESCRIPTION:
CATEGORY:
Astronomy
CALLING SEQUENCE:
lonstr, longitude, places, str
INPUTS:
longitude - Longitude, in radians, to be converted to a string. May
a vector, in which case the output will be a vector.
places - Resolution of output string.
= -7 nearest hour. +DD
= -6 nearest 30 minutes. +DD:(00,30)
= -5 nearest 15 minutes. +DD:(00,15,30,45)
= -4 nearest 10 minutes. +DD:M0
= -3 nearest 5 minutes. +DD:M(0,5)
= -2 nearest minute. +DD:MM
= -1 nearest ten seconds. +DD:MM:S0
= 0 nearest second. +DD:MM:SS
= 1 nearest tenth of a second. +DD:MM:SS.s
= 2 nearest hundredth of a second. +DD:MM:SS.ss
= 3 nearest thousandth of a second. +DD:MM:SS.sss
OPTIONAL INPUT PARAMETERS:
KEYWORD PARAMETERS:
SEPCHAR - Separator character for the fields in the position.
Default=':'. Warning, if you do not use ':' then the
string may not be parsable by raparse.
FORMAT = 'E' for east longitude, 'W' for west long. Default = positive.
OUTPUTS:
str - Output string for the converted longitude.
COMMON BLOCKS:
SIDE EFFECTS:
RESTRICTIONS:
PROCEDURE:
East longitude (in the range [-pi,pi]) is converted to a string.
The sign of the longitude is always provided and there are no imbedded
blanks. PLACES indicates the reported precision of the string.
Calls external routine radtodms.
MODIFICATION HISTORY:
Copyright (C) 1987,91, by Marc W. Buie
Version dated 91/8/5
Ported by Doug Loucks, Lowell Observatory, August 11, 1993, from the
C-Language version written by Marc Buie.
2003/05/09, MWB, added SEPCHAR keyword
(See astronomy/lonstr.pro)
NAME:
lonstrf
PURPOSE: (one line)
Convert longitude in radians to an ASCII string.
DESCRIPTION:
CATEGORY:
Astronomy
CALLING SEQUENCE:
str = lonstrf(lon, places)
INPUTS:
lon - Longitude, in radians, to be converted to a string. May
a vector, in which case the output will be a vector.
OPTIONAL INPUT PARAMETERS:
places - Resolution of output string (integer).
= -7 nearest hour. +DD
= -6 nearest 30 minutes. +DD:(00,30)
= -5 nearest 15 minutes. +DD:(00,15,30,45)
= -4 nearest 10 minutes. +DD:M0
= -3 nearest 5 minutes. +DD:M(0,5)
= -2 nearest minute. +DD:MM
= -1 nearest ten seconds. +DD:MM:S0
= 0 nearest second. +DD:MM:SS
= 1 nearest tenth of a second. +DD:MM:SS.s
= 2 nearest hundredth of a second. +DD:MM:SS.ss
= 3 nearest thousandth of a second. +DD:MM:SS.sss
KEYWORD INPUT PARAMETERS:
SEPCHAR - Separator character for the fields in the position.
Default=':'. Warning, if you do not use ':' then
the
string may not be parsable by raparse.
FORMAT = 'E' for east longitude, 'W' for west long. Default =
positive.
KEYWORD OUTPUT PARAMETERS:
none
OUTPUTS:
str - Output string for the converted lon
COMMON BLOCKS:
SIDE EFFECTS:
RESTRICTIONS:
PROCEDURE:
Call the PROCEDURE lonstr
MODIFICATION HISTORY:
Written 2006 Feb 27, by Leslie Young, SwRI
(See astronomy/lonstrf.pro)
NAME: planck_nu PURPOSE: (one line) Return Planck function (brightness of a blackbody) in erg/cm^2/s/Hz DESCRIPTION: Return Planck function (brightness of a blackbody) in erg/cm^2/s/Hz CATEGORY: Astronomy CALLING SEQUENCE: b = planck_nu(t, nu) INPUTS: t - temperature in K nu - frequency (Hz) OPTIONAL INPUT PARAMETERS: none KEYWORD INPUT PARAMETERS: none KEYWORD OUTPUT PARAMETERS: none OUTPUTS: Planck function COMMON BLOCKS: uses share_physconst SIDE EFFECTS: RESTRICTIONS: Must run phys_const first For now, T and nu are scalars PROCEDURE: MODIFICATION HISTORY: Written 2000 April, by Leslie Young, SwRI Modified Jan 2001 LAY SwRI
(See astronomy/planck_nu.pro)
NAME: radec2xyz PURPOSE: (one line) Convert from ra, dec to xyz DESCRIPTION: Convert from ra, dec to xyz CATEGORY: Astronomy CALLING SEQUENCE: xyz = radec2xyz(radec) INPUTS: radec - vector of [ra, dec] in radians OPTIONAL INPUT PARAMETERS: none KEYWORD INPUT PARAMETERS: none KEYWORD OUTPUT PARAMETERS: none OUTPUTS: xyz - vector of [x,y,z] COMMON BLOCKS: None SIDE EFFECTS: RESTRICTIONS: None PROCEDURE: MODIFICATION HISTORY: Written 2000, by Leslie Young, SwRI 2005 Apr 26 do arithmatic in doubles
(See astronomy/radec2xyz.pro)
NAME:
radrec6
PURPOSE: (one line)
Convert from [r, ra, dec, r', ra', dec'] to [f,g,h,f',g',h']
DESCRIPTION:
Convert from [r, ra, dec, r', ra', dec'] to [f,g,h,f',g',h']
CATEGORY:
Astronomy
CALLING SEQUENCE:
fghstate = rad6fgh6(rad6, radec_star, dradec_star)
INPUTS:
rad6 - vector of
r - range in LENGTH UNITS (eg km)
ra - right ascention in radians
dec - declination in radians
r' - range derivative in LENGTH/TIME (km/s)
ra' - right ascention derivative in radians/TIME (NOT cosdec dra/dt)
dec' - declination derivative in radians/TIME
radec_star - vector of;
A - right ascention in radians
D - declination in radians
OPTIONAL INPUT PARAMETERS:
dradec_star - vector of [dA, dD]
dA = d(A)/dt (NOT cosdec dA/dt)
dD = dD/dt
KEYWORD INPUT PARAMETERS:
none
KEYWORD OUTPUT PARAMETERS:
none
OUTPUTS:
fgh6 - vector of [f,g,h,f',g',h']
f - distance on F axis in units of LENGTH
g - distance on G axis in units of LENGTH
h - distance on H axis in units of LENGTH
f' - f derivative in LENGTH/TIME
g' - g derivative in LENGTH/TIME
h' - h derivative in LENGTH/TIME
fgh are distances along unit vectors IJK, as defined in
Green Spherical Astronomy, sec 13.2.
K - in the direction of star (A,D)
I - perpendicular to K and celestial N pole ("East on sky")
J - perpendicular to I and K ("North on sky")
If r is in km, r' in km/s, and ra' and dec' in radian/s,
then f, g, and h are in km and f', g' and h' are in km/s
COMMON BLOCKS:
None
SIDE EFFECTS:
RESTRICTIONS:
None
PROCEDURE:
This method is slightly preferred over rec6fgh6 when the
fundemental calculated variables are ra, dec
MODIFICATION HISTORY:
Written 2006 Jan 02 Leslie Young
2006 May 11 LAY corrected documentation
(See astronomy/rad6fgh6.pro)
NAME: radrec6 PURPOSE: (one line) Convert from [r, ra, dec, r', ra', dec'] to [x,y,z,x',y',z'] DESCRIPTION: Convert from [r, ra, dec, r', ra', dec'] to [x,y,z,x',y',z'] CATEGORY: Astronomy CALLING SEQUENCE: state = rad6rec6(rad6) INPUTS: rad6 - vector of r - range in LENGTH UNITS ra - right ascention in radians dec - declination in radians r' - range derivative in LENGTH/TIME ra' - right ascention derivative in radians/TIME dec' - declination derivative in radians/TIME OPTIONAL INPUT PARAMETERS: none KEYWORD INPUT PARAMETERS: none KEYWORD OUTPUT PARAMETERS: none OUTPUTS: rec6 - vector of [x,y,z,x',y',z'] x - distance on X axis in units of LENGTH y - distance on Y axis in units of LENGTH z - distance on Z axis in units of LENGTH x' - x derivative in LENGTH/TIME y' - y derivative in LENGTH/TIME z' - z derivative in LENGTH/TIME If r is in km, r' in km/s, and ra' and dec' in radian/s, then x, y, and z will be in km, and x', y', z' in km/s (e.g., the same format as states returned by spice routines) COMMON BLOCKS: None SIDE EFFECTS: RESTRICTIONS: None PROCEDURE: MODIFICATION HISTORY: Written 2005 Apr 26, by Leslie Young, SwRI 2006 Mar 11 LAY correct documentation
(See astronomy/rad6rec6.pro)
NAME:
radrec6
PURPOSE: (one line)
Convert from [x,y,z,x',y',z'] to [f,g,h,f',g',h']
DESCRIPTION:
Convert from [x,y,z,x',y',z'] to [f,g,h,f',g',h']
CATEGORY:
Astronomy
CALLING SEQUENCE:
fgh6 = rec6fgh6(rec6, radec_star, dradec_star)
INPUTS:
rec6 - vector of [x,y,z,x',y',z']
x - distance on X axis in units of LENGTH
y - distance on Y axis in units of LENGTH
z - distance on Z axis in units of LENGTH
x' - x derivative in LENGTH/TIME
y' - y derivative in LENGTH/TIME
z' - z derivative in LENGTH/TIME
radec_star - vector of [A,D]
A - right ascention in radians
D - declination in radians
OPTIONAL INPUT PARAMETERS:
dradec_star - vector of [dA, dD]
dA = d(A)/dt (NOT cosdec dA/dt)
dD = dD/dt
KEYWORD INPUT PARAMETERS:
none
KEYWORD OUTPUT PARAMETERS:
none
OUTPUTS:
fgh6 - vector of [f,g,h,f',g',h']
fgh are distances along unit vectors IJK, as defined in
Green Spherical Astronomy, sec 13.2.
K - in the direction of star (A,D)
I - perpendicular to K and celestial N pole ("East on sky")
J - perpendicular to I and K ("North on sky")
If x, y, and z are in km, and x', y', z' in km/s
(e.g., the same format as states returned by spice routines)
then f, g, and h are km, and f', g', and h' are in km/s
COMMON BLOCKS:
None
SIDE EFFECTS:
RESTRICTIONS:
None
PROCEDURE:
MODIFICATION HISTORY:
Written 2006 Jan 02, by Leslie Young, SwRI
2006 Mar 11 LAY. Corrected decumentation
(See astronomy/rec6fgh6.pro)
NAME: radrec6 PURPOSE: (one line) Convert from [x,y,z,x',y',z'] to [r, ra, dec, r', ra', dec'] DESCRIPTION: Convert from [x,y,z,x',y',z'] to [r, ra, dec, r', ra', dec'] CATEGORY: Astronomy CALLING SEQUENCE: rad6 = rec6rad6(rad6) INPUTS: rec6 - vector of [x,y,z,x',y',z'] x - distance on X axis in units of LENGTH y - distance on Y axis in units of LENGTH z - distance on Z axis in units of LENGTH x' - x derivative in LENGTH/TIME y' - y derivative in LENGTH/TIME z' - z derivative in LENGTH/TIME OPTIONAL INPUT PARAMETERS: none KEYWORD INPUT PARAMETERS: none KEYWORD OUTPUT PARAMETERS: none OUTPUTS: rad6 - vector of r - range in LENGTH UNITS ra - right ascention in radians dec - declination in radians r' - range derivative in LENGTH/TIME ra' - right ascention derivative in radians/TIME dec' - declination derivative in radians/TIME If x, y, and z are in km, and x', y', z' in km/s (e.g., the same format as states returned by spice routines) then r will be in km, r' in km/s, and ra' and dec' in radian/s, COMMON BLOCKS: None SIDE EFFECTS: RESTRICTIONS: None PROCEDURE: MODIFICATION HISTORY: Written 2005 Apr 26, by Leslie Young, SwRI 2006 Mar 11 LAY, corrected documentation
(See astronomy/rec6rad6.pro)
NAME:
rastrf
PURPOSE: (one line)
turn ra (radian) into hh:mm:ss[.SSS] as a function
DESCRIPTION:
CATEGORY:
Astronomy
CALLING SEQUENCE:
str = rastrf(ra, places, carry)
INPUTS:
ra - right ascention (radians)
OPTIONAL INPUT PARAMETERS:
places - Resolution of output string (integer).
= -8 Decimal hours HH.hhhhh
= -7 nearest hour. HH
= -6 nearest 30 minutes. HH:(00,30)
= -5 nearest 15 minutes. HH:(00,15,30,45)
= -4 nearest 10 minutes. HH:M0
= -3 nearest 5 minutes. HH:M(0,5)
= -2 nearest minute. HH:MM
= -1 nearest ten seconds. HH:MM:S0
= 0 nearest second. HH:MM:SS
= 1 nearest tenth of a second. HH:MM:SS.s
= 2 nearest hundredth of a second. HH:MM:SS.ss
= 3 nearest thousandth of a second. HH:MM:SS.sss
= 4 nearest thousandth of a second. HH:MM:SS.ssss DEFAULT
KEYWORD INPUT PARAMETERS:
none
KEYWORD OUTPUT PARAMETERS:
none
OUTPUTS:
str - Output string for the converted right ascension.
carry - Flag that indicates ra rolled over after rounding.
COMMON BLOCKS:
SIDE EFFECTS:
RESTRICTIONS:
PROCEDURE:
Call the PROCEDURE rastr
MODIFICATION HISTORY:
Written 2006 Feb 27, by Leslie Young, SwRI
(See astronomy/rastrf.pro)
NAME: rd2ang PURPOSE: (one line) pairs of ra,dec coordinates to great-circle angle DESCRIPTION: CATEGORY: Astronomy CALLING SEQUENCE: ang = rd2ang(A, D, ra, dec) INPUTS: A - ra of point 1 (radians) D - dec of point 1 (radians) ra - ra of point 2 (radians) dec -dec of point 2 (radians) OPTIONAL INPUT PARAMETERS: none KEYWORD INPUT PARAMETERS: none KEYWORD OUTPUT PARAMETERS: none OUTPUTS: ang - angle between two points (radians) COMMON BLOCKS: SIDE EFFECTS: RESTRICTIONS: PROCEDURE: MODIFICATION HISTORY: Written 2006 Mar 5, by Leslie Young, SwRI
(See astronomy/rd2ang.pro)
NAME: xieta2rd PURPOSE: (one line) ra,dec coordinates to xi, eta DESCRIPTION: CATEGORY: Astronomy CALLING SEQUENCE: rd2xieta, A, D, ra, dec, xi, eta INPUTS: A - ra of the center of a plane (radians) D - dec of the center of the plane (radians) ra - ra of the point (radians) dec -dec of the point (radians) OPTIONAL INPUT PARAMETERS: none KEYWORD INPUT PARAMETERS: none KEYWORD OUTPUT PARAMETERS: none OUTPUTS: xi - distance east of a point from center of plane (radians) eta - distance north of a point from center of plane (radians) COMMON BLOCKS: SIDE EFFECTS: RESTRICTIONS: PROCEDURE: For a plane centered at A, D, find the tangent point coordinates xi, eta cooresponding to a target at ra, dec Smart, Text-book on spherical astronomy, 5th ed, section 161 MODIFICATION HISTORY: Written 2005 Jan 27, by Leslie Young, SwRI Moved to $layoung/astronomy 2005 Mar 5
(See astronomy/rd2xieta.pro)
NAME: xieta2rd PURPOSE: (one line) xi,eta coordinates to ra, dec DESCRIPTION: CATEGORY: Astronomy CALLING SEQUENCE: xieta2rd, A, D, xi, eta, ra, dec INPUTS: A - ra of the center of a plane (radians) D - dec of the center of the plane (radians) xi - distance east of a point from center of plane (radians) eta - distance north of a point from center of plane (radians) OPTIONAL INPUT PARAMETERS: none KEYWORD INPUT PARAMETERS: none KEYWORD OUTPUT PARAMETERS: none OUTPUTS: ra - ra of the point (radians) dec -dec of the point (radians) COMMON BLOCKS: SIDE EFFECTS: RESTRICTIONS: PROCEDURE: For a plane centered at A, D, find the ra, dec for the given tangent point coordinates xi, eta cooresponding to a target at ra, dec Green, eq. 13.13 MODIFICATION HISTORY: Written 2005 Jan 27, by Leslie Young, SwRI Moved to $layoung/astronomy 2005 Mar 5
(See astronomy/xieta2rd.pro)
NAME: xyz2radec PURPOSE: (one line) Convert from xyz to ra, dec DESCRIPTION: Convert from xyz to ra, dec CATEGORY: Astronomy CALLING SEQUENCE: radec = xyz2radec(xyz) INPUTS: xyz - vector of [x,y,z] OPTIONAL INPUT PARAMETERS: none KEYWORD INPUT PARAMETERS: none KEYWORD OUTPUT PARAMETERS: none OUTPUTS: radec - vector of [ra, dec] in radians COMMON BLOCKS: None SIDE EFFECTS: RESTRICTIONS: None PROCEDURE: MODIFICATION HISTORY: Written 2000, by Leslie Young, SwRI 2006 Jan 12 LAY change to doubles.
(See astronomy/xyz2radec.pro)