;+ ; Project : SOHO - CDS ; ; Name : GET_VDS_SLITPOS ; ; Purpose : Gets VDS state database information. ; ; Explanation : This returns a structure containing information about various ; quasi-static VDS parameters. ; ; Use : GET_VDS_SLITPOS, DATE, DESC, ERRMSG=ERRMSG ; ; Inputs : DATE = The date/time value that the user wishes the state ; for. This can be in any of the standard CDS time ; formats. ; ; Opt. Inputs : None. ; ; Outputs : DESC = Structure containing the state description. It ; contains the following tags: ; ; DATE = Start date and time for the period for ; which the parameters in this record are ; valid. The period ends at the start ; date/time of the next record. This is a ; double precision TAI value. If no entries ; are found, then a simplified structure is ; returned with this set to zero. ; N1_CEN_S = Center slit position for NIS1 at the short ; wavelength end. ; N1_CEN_L = Center slit position for NIS1 at the long ; wavelength end. ; N2_CEN_S = Center slit position for NIS2 at the short ; wavelength end. ; N2_CEN_L = Center slit position for NIS2 at the long ; wavelength end. ; NIS_HT = NIS slit height. ; ; Opt. Outputs: None. ; ; Keywords : ; ERRMSG = If defined and passed, then any error messages will be ; returned to the user in this parameter rather than ; depending on the MESSAGE routine in IDL. If no errors are ; encountered, then a null string is returned. In order to ; use this feature, ERRMSG must be defined first, e.g. ; ; ERRMSG = '' ; GET_STATE, ERRMSG=ERRMSG, ... ; IF ERRMSG NE '' THEN ... ; ; Calls : DATATYPE, CP_GET_HISTORY, ANYTIM2UTC, UTC2TAI. ; ; Common : None. ; ; Restrictions: None. ; ; Side effects: None. ; ; Category : Command preparation. ; ; Prev. Hist. : Adapted from CP_GET_STATE by Martin Carter. ; ; Written : William Thompson, GSFC, 22 February 1996 ; ; Modified : Version 1, William Thompson, GSFC, 22 February 1996 ; Adapted from CP_GET_STATE. Only returns readout mode ; and MCP voltage. ; Version 2, William Thompson, GSFC, 29 February 1996 ; Added NIS_HT to output structure. ; Version 3, Peter Young, GMU, 21 June 2011 ; Changed 'list' to 'dlist' for compatibility ; with IDL 8. ; ; Version : Version 3, 21 June 2011 ;- ;********************************************************** PRO get_vds_slitpos, date, desc, ERRMSG=ERRMSG ON_ERROR, 2 ; ; Define a null result. If the routine is successful, this will be updated ; later. ; desc = {date: 0} ; ; Check the number of parameters. ; IF N_PARAMS() NE 2 THEN BEGIN MESSAGE = 'Syntax: GET_VDS_SLITPOS, DATE, DESC' GOTO, HANDLE_ERROR ENDIF ; ; Check the input parameter. ; IF N_ELEMENTS(date) NE 1 THEN BEGIN MESSAGE = 'DATE must be a scalar' GOTO, HANDLE_ERROR ENDIF ; ; Convert the date to TAI format. ; IF DATATYPE(date,1) EQ 'Double' THEN tai = date ELSE $ tai = UTC2TAI(date) ; ; get VDS parameters from state database ; get N1_CEN_S s = cp_get_history ( {mnemonic:'N1_CEN_S', pnumber:0}, /QUIET ) IF s(0).mnemonic EQ 'Unknown' THEN BEGIN MESSAGE = 'PARAMETER N1_CEN_S NOT FOUND IN CDHS STATE DATABASE' GOTO, HANDLE_ERROR ENDIF ; look for dates before given date for item dlist = WHERE ( UTC2TAI ( ANYTIM2UTC ( s.date ) ) LE tai, count ) IF count EQ 0 THEN BEGIN message, /informational, 'Using first value for N1_CEN_S' dlist = where( s.date eq min(s.date), count ) ENDIF ; get latest item s = s ( dlist(count-1) ) n1_cen_s = s.active st_date = UTC2TAI ( ANYTIM2UTC ( s.date ) ) ; get N1_CEN_L s = cp_get_history ( {mnemonic:'N1_CEN_L', pnumber:0}, /QUIET ) IF s(0).mnemonic EQ 'Unknown' THEN BEGIN MESSAGE = 'PARAMETER N1_CEN_L NOT FOUND IN CDHS STATE DATABASE' GOTO, HANDLE_ERROR ENDIF ; look for dates before given date for item dlist = WHERE ( UTC2TAI ( ANYTIM2UTC ( s.date ) ) LE tai, count ) IF count EQ 0 THEN BEGIN message, /informational, 'Using first value for N1_CEN_L' dlist = where( s.date eq min(s.date), count ) ENDIF ; get latest item s = s ( dlist(count-1) ) n1_cen_l = s.active st_date = st_date > UTC2TAI ( ANYTIM2UTC ( s.date ) ) ; get N2_CEN_S s = cp_get_history ( {mnemonic:'N2_CEN_S', pnumber:0}, /QUIET ) IF s(0).mnemonic EQ 'Unknown' THEN BEGIN MESSAGE = 'PARAMETER N2_CEN_S NOT FOUND IN CDHS STATE DATABASE' GOTO, HANDLE_ERROR ENDIF ; look for dates before given date for item dlist = WHERE ( UTC2TAI ( ANYTIM2UTC ( s.date ) ) LE tai, count ) IF count EQ 0 THEN BEGIN message, /informational, 'Using first value for N2_CEN_S' dlist = where( s.date eq min(s.date), count ) ENDIF ; get latest item s = s ( dlist(count-1) ) n2_cen_s = s.active st_date = st_date > UTC2TAI ( ANYTIM2UTC ( s.date ) ) ; get N2_CEN_L s = cp_get_history ( {mnemonic:'N2_CEN_L', pnumber:0}, /QUIET ) IF s(0).mnemonic EQ 'Unknown' THEN BEGIN MESSAGE = 'PARAMETER N2_CEN_L NOT FOUND IN CDHS STATE DATABASE' GOTO, HANDLE_ERROR ENDIF ; look for dates before given date for item dlist = WHERE ( UTC2TAI ( ANYTIM2UTC ( s.date ) ) LE tai, count ) IF count EQ 0 THEN BEGIN message, /informational, 'Using first value for N2_CEN_L' dlist = where( s.date eq min(s.date), count ) ENDIF ; get latest item s = s ( dlist(count-1) ) n2_cen_l = s.active st_date = st_date > UTC2TAI ( ANYTIM2UTC ( s.date ) ) ; get NIS_HT s = cp_get_history ( {mnemonic:'NIS_HT', pnumber:0}, /QUIET ) IF s(0).mnemonic EQ 'Unknown' THEN BEGIN MESSAGE = 'PARAMETER NIS_HT NOT FOUND IN CDHS STATE DATABASE' GOTO, HANDLE_ERROR ENDIF ; look for dates before given date for item dlist = WHERE ( UTC2TAI ( ANYTIM2UTC ( s.date ) ) LE tai, count ) IF count EQ 0 THEN BEGIN message, /informational, 'Using first value for NIS_HT' dlist = where( s.date eq min(s.date), count ) ENDIF ; get latest item s = s ( dlist(count-1) ) nis_ht = s.active st_date = st_date > UTC2TAI ( ANYTIM2UTC ( s.date ) ) ; set up output structure desc = {date: st_date, $ n1_cen_s: n1_cen_s, $ n1_cen_l: n1_cen_l, $ n2_cen_s: n2_cen_s, $ n2_cen_l: n2_cen_l, $ nis_ht: nis_ht} RETURN ; ; Error handling point. ; HANDLE_ERROR: IF N_ELEMENTS(ERRMSG) NE 0 THEN ERRMSG = 'GET_VDS_SLITPOS: '+MESSAGE $ ELSE MESSAGE, MESSAGE END