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NAME: CONS_COO PURPOSE: Return a set of X or Y pixel values given an image with astrometry, and either (1) a set of Y OR X pixel values, and a scalar right ascension, or (2) a set of right ascension values, and a scalar Y OR X value. In usage (1), CONS_COO can be used to determine the (X,Y) values of a line of constant right ascension. In usage (2), CONS_COO can used to determine the X positions of specified RA values, along a line of constant Y. CALLING SEQUENCE: X = CONS_COO( COO, xy, h) INPUTS: coo - coordinate value in RADIANS (0 < RA < 2*PI). If Y is a vector, then RA must be a scalar XY - Specified Y pixel value(s) for line of constant right ascension If RA is a vector, then Y must be a scalar CD - 2 x 2 Matrix in RADIANS giving the values of the CD astrometry parameters. CRPIX-2 element vector giving the X and Y coordinates of the reference pixel (exactly as given in a FITS header). CRVAL-2 element vector giving right ascension and declination in RADIANS of the reference pixel. OUTPUTS X - Computed set of X pixel values. The number of elements of X is the maximum of the number of elements of RA and Y. RESTRICTIONS: Program will have difficulty converging for declination values near 90. A tangent projection is assumed REVISION HISTORY: Written, Wayne Landsman STX Co. April, 1988 Algorithm adapted from AIPS memo No. 27 by Eric Griessen
(See MacintoshHD:IDL Libraries:JPBlib:Coordinates:cons_coo.pro)
NAME:
coo2co
PURPOSE:
Converts fits-like coordonates description to COBE-like
(e.g. 'RA' into 'q')
CALLING SEQUENCE:
res=coo2co(proj)
INPUTS:
proj : Fits-like projection type, ie 'RA', 'GLON' or 'ECLON'
OUTPUTS
res : Dirbe-like projection type, ie 'q','g','e'
RESTRICTIONS:
None
REVISION HISTORY:
Bernard J.P., a long time ago
(See MacintoshHD:IDL Libraries:JPBlib:Coordinates:coo2co.pro)
NAME:
coo2pix2
PURPOSE:
converts coordinates to pixels for a certain projection
CATEGORY:
Coordinates conversions
CALLING SEQUENCE:
coo2pix2,c1,c2,pixx,pixy[,phi,theta]
INPUTS:
c1,c2 (coordinates degrees)
OPTIONAL INPUT PARAMETERS:
OUTPUTS:
pixx = x pixel value (IDL format)
pixy = y pixel value (IDL format)
OPTIONAL OUTPUT PARAMETERS:
theta, phi = native spherical coordinates
ACCEPTED KEY-WORDS:
projection = set to force the proj type (otherwise from common)
silent = for the program to be silent
lbl = line by line processing, to save memory space
COMMON BLOCKS:
proj_common.com
SIDE EFFECTS:
RESTRICTIONS:
PROCEDURE:
like coo2pix, but performs the calculation on the array at once
(not line by line)
pixx and pixy are centered at the projection center
sxpar,my_ll2uv,my_uv2ll,apply_proj2
EXAMPLES
MODIFICATION HISTORY:
Written by J.P. Bernard Mar 20 1995
Modified JPB 8/7/99 to use non 2D coordinates arrays
(See MacintoshHD:IDL Libraries:JPBlib:Coordinates:coo2pix2.pro)
NAME:
cor_proj_cod
CATEGORY:
JPBLib Coordinates conversions
PURPOSE:
converts coordinates and projection types into a valid fits ctype
CALLING SEQUENCE:
cor_proj_cod,coord,proj,ctype1,ctype2,status
INPUT:
coord : Type of ccordinates
proj : type of projection
OUTPUT:
ctype1 : fits ctype1 sting
ctype2 : fits ctype2 sting
status : status =0 if OK
OPTIONAL INPUT:
None
INPUT KEYWORDS:
None
OUTPUT KEYWORDS:
None
SIDE EFFECTS:
None
EXAMPLES:
cor_proj_cod,'DEC','TAN',ctype1,ctype2,status
IDL> print,ctype1,ctype2
DEC--TAN
RA---TAN
RESTRICTIONS:
None
PROCEDURES CALLED:
None
REVISION HISTORY:
Created by Bernard Jean-Philippe Jan 31 1995
(See MacintoshHD:IDL Libraries:JPBlib:Coordinates:cor_proj_cod.pro)
NAME:
cor_proj_dec
CATEGORY:
JPBLib Coordinates conversions
PURPOSE:
decodes ctype keyword value into coordinate and projection type
CALLING SEQUENCE:
cor_proj_dec,ctype,coord,proj,projtype,status,silent=silent
INPUTS:
ctype = ctype value (e.g. 'RA---TAN')
OPTIONAL INPUT PARAMETERS:
OUTPUTS:
coord = coordinate system (e.g. 'RA')
proj = projection (e.g. 'TAN')
projtype = projection type (e.g. 'ZEN')
status = 1 if OK, 0 otherwise
OPTIONAL OUTPUT PARAMETERS:
ACCEPTED KEY-WORDS:
silent = If set keeps silent
COMMON BLOCKS:
SIDE EFFECTS:
RESTRICTIONS:
PROCEDURE:
Straightforward.
Uses : remchar
MODIFICATION HISTORY:
Written Jan 31 1995 J.P. Bernard, IPAC.
(See MacintoshHD:IDL Libraries:JPBlib:Coordinates:cor_proj_dec.pro)
NAME:
create_coo2
PURPOSE:
CREATE_coo creates coordinates from any fits header
CATEGORY:
Coordinates conversions
CALLING SEQUENCE:
CREATE_COO2,H,coo1,coo2
INPUTS:
h= the header
OPTIONAL INPUT PARAMETERS:
OUTPUTS:
coo1 = latitude (degrees)
coo2 = longitude (degrees)
OPTIONAL OUTPUT PARAMETERS:
ACCEPTED KEY-WORDS:
lbl = line by line processing
silent = If set keeps silent
remove_edge = if set bad coordinates at edges are set to
!indef. Necessary for projections such as GLS,
etc ..
COMMON BLOCKS:
SIDE EFFECTS:
RESTRICTIONS:
PROCEDURE:
Creates 1D or 2D arrays of coordinates in a given projection.
The parameters are taken from the fits header h, unless specified
in keywords (e.g proj).
Uses the 3 step procedure described by Greisen & Calabretta (Fits
standards).
Output coordinates are in degrees, and areas with no coordinates
are filled with undefined values (-32768). Longitude increase toward
right for cdelt > 0
Currently recognized projection types are:
CAR Cartesian
GLS Global Sinusoidal
MOL Mollweide's
AIT Aitoff
Uses :sxpar,pix2coo
MODIFICATION HISTORY:
Written Jan 31 1995 J.P. Bernard, IPAC.
(See MacintoshHD:IDL Libraries:JPBlib:Coordinates:create_coo2.pro)
NAME:
h2pix
PURPOSE:
creates pixel array from a header and initialize the projection common
CATEGORY:
Coordinates conversions
CALLING SEQUENCE:
pix2coo,h,pixx,pixy,coo1,coo2
INPUTS:
h= the header
OPTIONAL INPUT PARAMETERS:
OUTPUTS:
pixx= x pixel value (IDL format)
pixy= y pixel value (IDL format)
OPTIONAL OUTPUT PARAMETERS:
ACCEPTED KEY-WORDS:
proj = set to force the proj type (otherwise from header)
COMMON BLOCKS:
proj_common defined in @proj_common
contains: mat,rot,proj,coord,naxis1,naxis2,crpix1,crpix2,projtype
SIDE EFFECTS:
RESTRICTIONS:
PROCEDURE:
The pixels values are 0 at the proj center (crpix1,crpix2)
The pixel array contains float values.
If only h is provided, only the common values are updated
If h,pixx are given, pixx is float(Naxis1*Naxis2,2) and the
first plane contains x pix values, the second y pix values.
If all arguments are provided, pixx and pixy are (Naxis1,Naxis2).
uses: sxpar
MODIFICATION HISTORY:
Written J.P. Bernard Mar 20 1995
(See MacintoshHD:IDL Libraries:JPBlib:Coordinates:h2pix.pro)
NAME:
make_gsfc_h
CALLING SEQUENCE:
make_gsfc_h,h
PURPOSE:
This is to create a header for the 1024*512 images created at GSFC
Restricted to the first realease zone: 213:298 (|b|<=15)
INPUTS:
OPTIONAL INPUT:
if FBB if set a header for the reduced image (1024,61) is done
allsky = make a all-sky header
coord = coordinate system
proj = projection type
sixpack = makes a 2000 eclipic sixpack cube header
tee = makes a 2000 eclipic unfolded Tee header
reso = resolution of the cube header (default=9)
OUTPUTS:
h = header to be created
PROCEDURE AND SUBROUTINE USED
mkhdr,write_header
SIDE EFFECTS:
none
MODIFICATION HISTORY:
written JPB Mon Nov 29 1993 @ IPAC
modif JPB Thu Feb 17 1994 @ IPAC to include /FBB and new ctype1 v1.1
modif JPB Fri Jan 27 1995 @ IPAC to put center at proj center
added coord and proj keywords
changed cdelt, added bunit
(See MacintoshHD:IDL Libraries:JPBlib:Coordinates:make_gsfc_h.pro)
NAME:
my_CCONV is a shell around pixel to unit vector to lon/lat
DESCRIPTION:
IDL function that acts as shell around the pixel <--> unit
vector, pixel <--> lon/lat, and unit vector <--> lon/lat
routines. It is called by COORCONV.
CALLING SEQUENCE:
output = convert(input,code)
ARGUMENTS (I = input, O = output, [] = optional):
input I arr Input coordinate array
code I int If > 0 then res else
uv <--> ll conversion
output O [arr] Output coordinate array
WARNINGS:
There is a C module linkimage by the same name that is a shell
around C functions that also perform conversions between pixels
and unit vectors and lon/lat. If this linkimage is not implemented
then this IDL procedure is compiled and run instead.
EXAMPLE:
Not user routine
#
COMMON BLOCKS:
None
PROCEDURE (AND OTHER PROGRAMMING NOTES):
Uses CASE statements to route the input through the proper
procedures.
PERTINENT ALGORITHMS, LIBRARY CALLS, ETC.:
Subroutines called: pix2uv, uv2pix, ll2uv, uv2ll
MODIFICATION HISTORY
Written by J.M. Gales, Applied Research Corp. Oct 92
Delivered 13-NOV-1992 SPR 10212
SPR 10316 Correct call to UV2LL
07-dec-1992 JM Gales
(See MacintoshHD:IDL Libraries:JPBlib:Coordinates:my_cconv.pro)
NAME:
my_COORCONV
DESCRIPTION:
IDL function that acts as shell around the various coordinate
conversion routines. It is the program that the user actually
calls. Input and output formats are pixel number, decimal
hour/latitude, longitude/latitude, and unit vector.
CALLING SEQUENCE:
outcoor = coorconv(in_coor,infmt=in_fmt,outfmt=out_fmt, $
inco=in_co, outco=out_co)
ARGUMENTS (I = input, O = output, [] = optional):
in_coor I [arr] Input coordinate array
infmt I str Input coordinate format
outfmt I str Output coordinate format
inco I str Input coord. system or resolution
outo I str Output coord. system or resolution
out_coor O [arr] Output coordinate array
where in_coor & out_coor arrays have the following dimensions
for n points:
Pixel - input_arr(n)
Decimal Hr/deg - input_arr(n,2)
lon/lat - input_arr(n,2)
Unit vector - input_arr(n,3)
infmt & outfmt are specified as follows:
Pixel - 'P'
Decimal Hr/dec - 'H'
Lon/Lat - 'L'
Unit vector - 'U'
If pixel number is the input format then inco (outco) is specified
as follows:
Firas (Res 6) - 'F' or 'R6'
DMR (Res 6) - 'D' or 'R6'
Dirbe (Res 9) - 'B' or 'R9'
Resolution m - 'Rm' where m is <= 15
(Note: The default coordinate system for pixels is ecliptic.)
otherwise use:
Ecliptic - 'E'
Galactic - 'G'
Equatorial - 'Q' (Epoch 2000)
Note: Lower case may also be used.
WARNINGS:
In order to optimize throughput, this routine does minimal data
checking. Improper input such as "unit" vectors with norm not
equal to one or pixel numbers with values outside the range
defined by the resolution will be processed without crashing,
however the output might lead to unexpected results. Therefore it
is up to the user to take proper care when generating and/or
passing the input.
The forward and inverse operations between pixel numbers and
pixel unit vector coordinates have been verified up to and
including resolution 12. (The forward procedure is based on
the forward_cube.for program in the upx directory.)
EXAMPLE:
To convert an array of sky coordinates in 'L' format from ecliptic
coordinates to an array in 'U' format in galactic coordinates:
output = coorconv(input,infmt='L',outfmt='U',inco='E',outco='G')
To convert an array of sky coordinates in 'L' format to an array in
'U' format without changing coordinate systems:
output = coorconv(input,infmt='L',outfmt='U')
To convert an array of sky coordinates in 'H' format in equatorial
coordinates to an array of Firas pixel numbers:
output = coorconv(input,infmt='H',outfmt='P',inco='Q',outco='F') or
output = coorconv(input,infmt='H',outfmt='P',inco='Q',outco='R7')
To convert an array of resolution 8 pixel numbers to sky coordinates
in 'L' format in galactic coordinates:
output = coorconv(input,infmt='P',outfmt='L',inco='R8',outco='G')
To convert an array of Dirbe pixel numbers to an array of DMR pixels:
output = coorconv(input,infmt='P',outfmt='p',inco='P',outco='D')
Note: You cannot "up res" pixel numbers from a lower resolution to a
higher one.
#
COMMON BLOCKS:
sky_conv_com
PROCEDURE (AND OTHER PROGRAMMING NOTES):
Uses CASE statements to route the input through the proper
procedures.
PERTINENT ALGORITHMS, LIBRARY CALLS, ETC.:
Subroutines called: loadsky, skyconv, cconv
MODIFICATION HISTORY
Written by J.M. Gales, Applied Research Corp. Mar 92
SPR 9741 Change PRINT statements to MESSAGE statements in
error situations.
2 JUN 1992
SER 9984 Implement cconv (c module for p <-> uv <-> ll conversions)
9-SEP-1992 JMG
SPR 10212 Generate conversions in call to CCONV module
Note: New CCONV exists as both IDL procedure and C module.
13-NOV-1992 JMG
SPR 10318 Fix problem with scalar pixel entry
07-DEC-1992 JMG
SPR 10348 Fix problem with integer format lon/lat and RA/dec input
Fix incorrect arithmetic in lon/lat <=> RA/dec conversion
14-DEC-1992 JMG
SPR 10842 Fix problem with conversion of long integers to short int
28-SEP-1993 JMG
.TITLE
Routine COORCONV
(See MacintoshHD:IDL Libraries:JPBlib:Coordinates:my_coorconv.pro)
NAME:
pix2coo2
PURPOSE:
converts pixels to coordinates given projection parameters
CATEGORY:
Coordinates conversions
CALLING SEQUENCE:
pix2coo2,pixx,pixy,coo1,coo2
INPUTS:
pixx= x pixel value (IDL format)
pixy= y pixel value (IDL format)
OPTIONAL INPUT PARAMETERS:
OUTPUTS:
coo1,coo2 (degrees)
OPTIONAL OUTPUT PARAMETERS:
ACCEPTED KEY-WORDS:
projection= set to force the proj type (otherwise from proj_common)
silent = for the program to be silent
lbl = line by line (to avoid out of memory pbs)
COMMON BLOCKS:
SIDE EFFECTS:
RESTRICTIONS:
PROCEDURE:
sxpar, apply_proj2, my_uv2ll, my_ll2uv
MODIFICATION HISTORY:
Written by J.P. Bernard Mar 20 1995
Modified JPB 8/7/99 to use non 2D coordinates arrays
(See MacintoshHD:IDL Libraries:JPBlib:Coordinates:pix2coo2.pro)
NAME:
WCSXY2SPH
PURPOSE:
To convert x and y (map) coordinates to spherical (longitude and
latitude or sky) coordinates. This procedure is the inverse of
WCSSPH2XY.
CATEGORY:
Mapping and Auxilliary FITS Routine
CALLING SEQUENCE:
wcsxy2sph, x, y, longitude, latitude, [map_type], [ CTYPE = ,$
FACE = ,PROJP1 = , PROJP2 = ,CRVAL =, CRXY =, LONGPOLE= ]
INPUT PARAMETERS:
x - x coordinate of data, scalar or vector, in degrees, NOTE: x
increases to to the left, not the right
y - y coordinate of data, same number of elements as x, in degrees
map_type - optional positional parameter, scalar corresponding to a
particular map projection. This is not a FITS standard, it is
simply put in to allow function similar to that of less general
map projection procedures (eg AITOFF). The following list gives
the map projection types and their respective numbers.
FITS Number Name Comments
code code
---- ------ ----------------------- -----------------------------------
DEF 0 Default = Cartesian
AZP 1 Zenithal perspective projp1 required
TAN 2 Gnomic AZP w/ projp1 = 0
SIN 3 Orthographic AZP w/ projp1 = Infinity (>10^14)
STG 4 Stereographic AZP w/ projp1 = 1
ARC 5 Zenithal Equidistant
ZPN 6 Zenithal polynomial prop1-projp9 required, useless
ZEA 7 Zenithal equal area
AIR 8 Airy projp1 required
CYP 9 Cylindrical perspective projp1 and projp2 required
CAR 10 Cartesian
MER 11 Mercator
CEA 12 Cylindrical equal area projp1 required
COP 13 Conical perspective projp1 and projp2 required
COD 14 Conical equidistant projp1 and projp2 required
COE 15 Conical equal area projp1 and projp2 required
COO 16 Conical orthomorphic projp1 and projp2 required
BON 17 Bonne's equal area projp1 required
PCO 18 Polyconic
GLS 19 Sinusoidal
PAR 20 Parabolic
AIT 21 Hammer-Aitoff
MOL 22 Mollweide
CSC 23 Cobe Quadrilateralized inverse converges poorly
Spherical Cube
QCS 24 Quadrilateralized
Spherical Cube
TSC 25 Tangential Spherical Cube
OPTIONAL KEYWORD PARAMETERS:
CTYPE - One, two, or three element vector containing 8 character
strings corresponding to the CTYPE1, CTYPE2, and CTYPE3
FITS keywords:
CTYPE(0) - first four characters specify standard system
('RA--','GLON' or 'ELON' for right ascension, galactic
longitude or ecliptic longitude respectively), second four
letters specify the type of map projection (eg '-AIT' for
Aitoff projection)
CTYPE(1) - first four characters specify standard sytem
('DEC-','GLAT' or 'ELAT' for declination, galactic latitude
or ecliptic latitude respectively; these must match
the appropriate system of ctype1), second four letters of
ctype2 must match second four letters of ctype1.
CTYPE(2) - if present must be the 8 character string,'CUBEFACE',
only used for spherical cube projections to identify an axis
as containing the face on which each x and y pair of
coordinates lie.
FACE - a input variable used for spherical cube projections to
designate the face of the cube on which the x and y
coordinates lie. Must contain the same number of elements
as X and Y.
CRVAL - 2 element vector containing standard system coordinates (the
longitude and latitude) of the reference point
CRXY - 2 element vector giving the x and y coordinates of the
reference point, if this is not set the offset of the x
coordinate is assumed to be 0.
LONGPOLE - native longitude of standard system's North Pole, default
is 180 degrees, numeric scalar
PROJP1 - scalar with first projection parameter, this may
or may not be necessary depending on the map projection used
PROJP2 - scalar with second projection parameter, this may
or may not be necessary depending on the map projection used
OUTPUT PARAMETERS:
longitude - longitude of data, same number of elements as x, in degrees
latitude - latitude of data, same number of elements as x, in degrees
NOTES:
The conventions followed here are ; in FITS" by Eric Greisen and
Mark Calabretta (draft dated August 16, 1994). The general scheme
outlined in that article is to convert x and y coordinates into a
"native" longitude and latitude and then rotate the system into one of
three generally recognized systems (celestial, galactic or ecliptic).
This procedure necessitates two basic sections. The first converts
x and y coordinates to "native" coordinates while the second converts
"native" to "standard" coordinates. The first section contains the
guts of the code in which all of the map projection is done. The
second step is performed by WCS_ROTATE and only involves rotation of
coordinate systems. WCSXY2SPH can be called in a form similar to
AITOFF, EQPOLE, or QDCB by calling wcsxy2sph with a fifth parameter
specifying the map projection by number and by not using any of the
keywords related to the map projection type (eg ctype1 and ctyp2).
PROCEDURE:
The first task of the procedure is to do general error-checking to
make sure the procedure was called correctly and none of the
parameters or keywords conflict. This is particularly important
because the procedure can be called in two ways (either using
FITS-type keywords or using a number corresponding a map projection
type). All variables are converted into double precision values.
The second task of the procedure is to take x and y coordinates and
convert them into "native" latitude and longitude coordinates.
Map-specific error-checking is done at this time. All of the
equations were obtained from "Representations of Celestial
Coordinates in FITS" and cases needing special attention are handled
appropriately (see the comments with individual map projections for
more information on special cases). WCS_ROTATE is then called to
convert the "native" coordinates to "standard" coordinates by rotating
the coordinate system. This rotation is governed by the keywords
CRVAL, and LONGPOLE. The transformation is a straightforward
application of euler angles. Finally, longitude values are converted
into the range from 0 to 360 degrees.
COMMON BLOCKS:
none
PROCEDURES CALLED:
WCS_ROTATE
COPYRIGHT NOTICE:
Copyright 1991, The Regents of the University of California. This
software was produced under U.S. Government contract (W-7405-ENG-36)
by Los Alamos National Laboratory, which is operated by the
University of California for the U.S. Department of Energy.
The U.S. Government is licensed to use, reproduce, and distribute
this software. Neither the Government nor the University makes
any warranty, express or implied, or assumes any liability or
responsibility for the use of this software.
AUTHOR:
Rick Balsano
MODIFICATIONS/REVISION LEVEL:
1.1 8/31/93
1.2 9/12/93 W. Landsman Vectorized CRXY, CRVAL, CTYPE
1.3 29/12/93 I. Freedman Eliminated LU decomposition
1.4 22/09/94 W. Landsman If scalar input, then scalar output
1.5 02/03/05 W. Landsman Change variable name BETA for V4.0 compatibility
1.6 06/07/05 W. Landsman Change loop index from integer to long
Adapted from above to include theta, phi Kwords J.P. Bernard.
(See MacintoshHD:IDL Libraries:JPBlib:Coordinates:my_wcsxy2sph.pro)