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Colorset idl9/3/2023 RA - Right ascension in decimal degrees, numeric scalar or vectorĭEC - Declination in decimal degrees, numeric scalar or vector RA_DEC - 2 element vector giving the Right Ascension and declination Of the declination in digits after the decimal point. RA and Dec may be entered as either a 2 element vector or as Return RA and Dec as character string in sexigesimal format. ![]() Landsman October 1998Ĭonsistent conversion between CROTA and CD matrix W. Understand reversed X,Y (X-Dec, Y-RA) axes, W. Landsman June 1995ĭon't subscript CTYPE W. 1994ĭo computation correctly in degrees W. *not* the FITS convention (first pixel is 1)Ĭonverted to IDL by B. X,Y will be in the standard IDL convention (first pixel is 0), and Y - column position in pixels, scalar or vector X - row position in pixels, scalar or vector CTYPE - 2 element vector giving projection types (def = NAXIS/2) in FITS convention (first pixel is 1,1) CRPIX - 2 element vector giving X and Y coordinates of reference pixel CDELT - 2 element vector giving increment at reference point in CD - 2 x 2 array containing the astrometry parameters CD1_1 CD1_2 For interactive purposes, use ADXY.ĪSTR - astrometry structure, output from EXTAST procedure containing: Landsman September 1997ĪD2XY Ĭompute X and Y from RA and DEC and a FITS astrometry structureĪ tangent (gnomonic) projection is computed directly other projectionsĪre computed using WCSXY2SPH. Use DEBUG keyword instead of !DEBUG September 1995Ĭonverted to IDL V5.0 W. DEBUG - If DEBUG is set, then ABSCAL will print theĬalibration units given by the BUNIT keyword. If the absolute calibration keywords do not exist, then ![]() RESULT = BSCALE*VALUE + BZERO, where the BSCALE and BZERO scalars Keyword BSCALE, and optionally BZERO and BUNIT. HEADER - A FITS header array containing the absolute calibration VALUE - Any scalar, vector, or array (usually an integer type giving a Routine Descriptions ABSCAL Īpply the FITS BZERO and BSCALE keyword values to a data array This routine, refer to the IDL Online Help Navigator This page was created by the IDL library routine
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