Function adstring,ra_dec,dec,precision ;+ ; NAME: ; ADSTRING ; PURPOSE: ; Return RA and Dec as character string(s) in sexigesimal format. ; EXPLANATION: ; RA and Dec may be entered as either a 2 element vector or as ; two separate vectors (or scalars). One can also specify the precision ; of the declination in digits after the decimal point. ; ; CALLING SEQUENCE ; result = ADSTRING( ra_dec, precision ) ; or ; result = ADSTRING( ra,dec,[ precision ] ) ; ; INPUTS: ; RA_DEC - 2 element vector giving the Right Ascension and declination ; in decimal degrees. ; or ; RA - Right ascension in decimal degrees, numeric scalar or vector ; DEC - Declination in decimal degrees, numeric scalar or vector ; ; OPTIONAL INPUT: ; PRECISION - Integer scalar (0-4) giving the number of digits after the ; decimal of DEClination. The RA is automatically 1 digit more. ; This parameter may either be the third parameter after RA,DEC ; or the second parameter after [RA,DEC]. It is not available ; for just DEC. If no PRECISION parameter is passed, a ; precision of 1 for both RA and DEC is returned to maintain ; compatibility with past ADSTRING functions. Values of ; precision larger than 4 will be truncated to 4. If ; PRECISION is 3 or 4, then RA and Dec should be input as ; double precision. ; ; OUTPUT: ; RESULT - Character string(s) containing HR,MIN,SEC,DEC,MIN,SEC formatted ; as ( 2I3,F5.(p+1),2I3,F4.p ) where p is the PRECISION ; parameter. If only a single scalar is supplied it is ; converted to a sexigesimal string (2I3,F5.1). ; ; EXAMPLE: ; (1) Display CRVAL coordinates in a FITS header, H ; ; IDL> crval = sxpar(h,'CRVAL*') ;Extract 2 element CRVAL vector (degs) ; IDL> print, adstring(crval) ;Print CRVAL vector sexigesimal format ; ; (2) print,adstring(30.42,-1.23,1) ==> ' 02 01 40.80 -01 13 48.0' ; print,adstring(30.42,+0.23) ==> ' 02 01 40.8 +00 13 48.0' ; print,adstring(+0.23) ==> '+00 13 48.0' ; ; (3) The first two calls in (2) can be combined in a single call using ; vector input ; print,adstring([30.42,30.42],[-1.23,0.23], 1) ; PROCEDURES CALLED: ; FSTRING(), RADEC, SIXTY() ; ; REVISION HISTORY: ; Written W. Landsman June 1988 ; Addition of variable precision and DEC seconds precision fix. ; ver. Aug. 1990 [E. Deutsch] ; Output formatting spiffed up October 1991 [W. Landsman] ; Remove ZPARCHECK call, accept 1 element vector April 1992 [W. Landsman] ; Call ROUND() instead of NINT() February 1996 [W. Landsman] ; Check roundoff past 60s October 1997 [W. Landsman] ; Work for Precision =4 November 1997 [W. Landsman] ; Converted to IDL V5.0 W. Landsman 24-Nov-1997 ; Major rewrite to allow vector inputs W. Landsman February 2000 ; Fix possible error in seconds display when Precision=0 ; P. Broos/W. Landsman April 2002 ;- On_error,2 Npar = N_params() case N_elements(ra_dec) of 1: if ( Npar EQ 1 ) then dec = ra_dec else ra = ra_dec 2: begin if (N_elements(dec) LT 2) then begin ra = ra_dec[0] mod 360. if N_elements(dec) EQ 1 then begin precision = dec & Npar=3 & endif dec = ra_dec[1] endif else ra = ra_dec end else: ra = ra_dec endcase if ( Npar GE 2 ) then $ if N_elements(dec) NE N_elements(ra) then message, $ 'ERROR - RA and Declintation do not have equal number of elements' if N_elements(ra) EQ N_elements(dec) then begin badrange = where( (dec LT -90.) or (dec GT 90.), Nbad) if Nbad GT 0 then message, /INF, $ 'WARNING - Some declination values are out of valid range (-90 < dec <90)' radec, ra, dec, ihr, imin, xsec, ideg, imn, xsc if (Npar LT 3) then precision = 0 precision = precision > 0 < 4 ;No more than 4 decimal places roundsec = [59.5,59.95,59.995,59.9995,59.99995,59.999995] carry = where(xsec GT roundsec[precision+1], Ncarry) if Ncarry GT 0 then begin imin[carry] = imin[carry] + 1 xsec[carry] = 0.0 mcarry = where(imin[carry] EQ 60, Nmcarry) if Nmcarry GT 0 then begin ic = carry[mcarry] ihr[ic] = ihr[ic] + 1 imin[ic] = 0 endif endif secfmt = '(F' + string( 4+precision+1,'(I1)' ) + '.' + $ string( precision+1,'(I1)' ) + ')' if (Npar LT 3) then precision = 1 result = fstring(ihr,'(I3.2)') + fstring(imin,'(I3.2)') + $ fstring(xsec,secfmt) + ' ' endif else begin x = sixty(dec) precision = 1 ideg = fix(x[0]) & imn = fix(x[1]) & xsc = x[2] result = '' endelse if ( precision EQ 0 ) then begin secfmt = '(I3.2)' xsc = round(xsc) carry = where(xsc EQ 60, Ncarry) if Ncarry GT 0 then begin ;Updated April 2002 xsc[carry] = 0 imn[carry] = imn[carry] + 1 endif endif else begin secfmt = '(F' + string( 4+precision,'(I1)') + '.' + $ string( precision,'(I1)') + ')' ixsc = fix(xsc + 0.5/10^precision) carry = where(ixsc GE 60, Ncarry) if Ncarry GT 0 then begin xsc[carry] = 0. imn[carry] = imn[carry] + 1 endif endelse pos = dec GT 0 carry = where(imn EQ 60, Ncarry) if Ncarry GT 0 then begin ideg[carry] = ideg[carry] -1 + 2*pos[carry] imn[carry] = 0 endif deg = fstring(ideg,'(I3.2)') zero = where(ideg EQ 0, Nzero) if Nzero GT 0 then begin negzero = where( (imn[zero] LT 0) or (xsc[zero] LT 0), Nneg) if Nneg GT 0 then begin ineg = zero[negzero] deg[ineg] = '-00' imn[ineg] = abs(imn[ineg]) & xsc[ineg] = abs(xsc[ineg]) endif endif ipos = where(pos, Npos) if Npos GT 0 then deg[ipos] = '+' + strtrim(deg[ipos],2) return, result + deg + fstring(imn,'(I3.2)') + fstring(xsc,secfmt) end