NAME:
	BadValue
 PURPOSE:
	Provide the Not A Number value for any data type
 CATEGORY:
	sat/idl/toolbox
 CALLING SEQUENCE:
	FUNCTION BadValue, X
 INPUTS:
	X	    variable of any type
 OUTPUTS:
	Result	    scalar; type: as implied by 'size' vector
			NaN value
 INCLUDE:
	@compile_opt.pro    ; On error, return to caller
 CALLS: ***
	IsType
 CALLED BY:
	AlignHeliosphere, CleanGlitchBox, Find2DGlitch, GeographicInfo
	InsituTimeSeries [1], InsituTimeSeries [2], IntegrateLOS
	InterpolateHeliosphere, LocalExtrema, MessengerOrbit, PlotBars, PlotCoronagraph
	PlotEarthSkymap, PlotEloTimeMap, PlotPolarSkymap, RemoteView_CurrentSheet
	RemoteView_Display2D, RemoteView_FOV_loc, RemoteView_Init_Matrix, StereoAOrbit
	StereoBOrbit, TMO_skymotion, TMO_tracksky, ThomsonMidpointFar, ThomsonPDistance
	ThomsonPDistanceFar, UlyssesOrbit, big_eph, cvsmei, eclipsed_area, even_light
	even_light_info, even_light_photometry, even_light_registration, flt_read
	flt_string, getnagoyasources, getootyasources, getsmeisources, jpl_eph, mpc_eph
	mpc_orbit_eph, nso_fe_temperature, physics_constant, qEphem_State, qGlitch_Run
	qImage_TrackPeak, qImage_cw_DrawCross, qImage_cw_Set_Value, qImage_cw_ZUpdate
	qImage_cw_ZWedge, qLine, qLine_Curve, qLine_IsX, qLine_XBase, qView_TMO_tracksky
	qvu, qvu_draw, sgp4_eph, sgp4_orbit_period, smei_ccd2sky, smei_findpnt
	smei_frm_base, smei_frm_summary, smei_hdr_get, smei_hdr_plot
	smei_plot_timeseries, smei_property, smei_sky, smei_sky2ccd, smei_sky_atlocation
	smei_sky_cleanedge_median, smei_sky_hdr2range, smei_sky_read, smei_sky_track
	smei_star_fit, smei_star_showsmooth, smei_zld_model, smei_zld_remove [1]
	smei_zld_remove [2], sphere_smooth, txt_block_read, usno_eph, vu_atlocation
	vu_correlate, vu_header, vu_insitu, vu_insitu_persist, vu_insitu_raw, vu_linecut
	vu_mean, vu_planarcut, vu_read, vu_solardisk, vu_timeseries, vu_type_insitu
	vu_type_skymap, vu_vox_write, wedge_content, wso_read
 PROCEDURE:
	For integers the number zero is returned.
	For floating point the appropriate value from !values is returned.
 MODIFICATION HISTORY:
	MAR-2000, Paul Hick (UCSD/CASS; pphick@ucsd.edu)

 NAME:
	bargraph
 PURPOSE:
	Plot bar graph
 CATEGORY:
	Plotting
 CALLING SEQUENCE:
	PRO bargraph, YY, sigma=sigma,	  $
	    minbin	= minbin	, $
	    maxbin	= maxbin	, $
	    bin 	= bin		, $
	    histo	= histo 	, $
	    hatch	= hatch 	, $
	    shade_color = shade_color	, $
	    xrange	= xrange	, $
	    yrange	= yrange	, $
	    title	= title 	, $
	    average	= average	, $
	    median	= median	, $
	    maximum	= maximum	, $
	    _extra	= _extra	, $
	    stat	= stat		, $
	    oplotx	= oplotx
 INPUTS:
	Y	array[n]; type: any numerical array
		    array to be plotted in bargraph
 OPTIONAL INPUTS:
	sigma=sigma scalar or array[n]; type: float
			errors in Y-array
			Ignored if /histo is set.
			If sigma is not a scalar, but does not have the
			same # elements as Y then it is ignored
	/histo	    if set the Y is passed through the IDL
			histogram function using keywords minbin, maxbin, bin
	minbin	    scalar; type: float; default: 0.0
			minimum X-value = left edge of leftmost bin
	bin	    scalar; type: float; default: 1.0
			bin width
	maxbin	    scalar; type: float
			maximum Y-value, only used as keyword to
			IDL histogram function if /histo is set

	/hatch	    if set and nonzero, bins will be hatched
	xrange=xrange
		    array[2]; type: float
			xrange keyword to IDL plot command
	yrange=yrange
		    array[2]; type: float
			yrange keyword to IDL plot command
	/average    if set, plot vertical line at position of average
	/median     if set, plot vertical line at position of median
	/maximum    if set, plot vertical line at position of maximum
	title	    scalar; type: string; default: value of bin width
		    title string
	_extra=_extra	additional keywords passed to IDL plot command
 OPTIONAL OUTPUTS:
	stat=stat   array[3]; type: float
		    positions of average, median and maximum
 INCLUDE:
	@compile_opt.pro	    ; On error, return to caller
 CALLS: ***
	InitVar, IsType, statpos
 CALLED BY:
	even_light_info, even_light_photometry, even_light_registration, qBar
 PROCEDURE:
 >	The number of bins is n_elements(Y)
 >	The bin edges are minbin+bin*indgen(n_elements(Y)+1)
 >	To plot a histogram of an array
	    bargraph,histogram(Y,min=25,max=350,bin=50),25,50
 MODIFICATION HISTORY:
	AUG-1992, Paul Hick (UCSD/CASS)
	    Modification of HIST.PRO (Written Feb'91 by DMZ (ARC))
	NOV-1992, Paul Hick (UCSD/CASS)
	    Added option to plot standard deviations
	JAN-2000, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
	    Minor modifications; added stat keyword

 NAME:
	BZero
 PURPOSE:

 CALLING SEQUENCE:
	FUNCTION BZero, T, degrees=degrees, lzero=L0
 INPUTS:
	T	array; type: standard time structure
		    times where B0 angle is requested
 OPTIONAL INPUT PARAMETERS:
	/degrees    if set, output angles BZero and L0 are in degrees
		(default: radians)
 OUTPUTS:
	Result	heliographic latitude of the sub-Earth point (center
		of the disk)
 OPTIONAL OUTPUT PARAMETERS:
	L0	heliographic longitude of the sub-Earth point
 INCLUDE:
	@compile_opt.pro	    ; On error, return to caller
 CALLS: ***
	SyncDims, big_eph, jpl_body
 PROCEDURE:
 >	For time T the heliocentric ecliptic longitude of the sub-Earth
	point is L=180+(geocentric ecliptic longitude Sun); the
	heliocentric latitude is D=-(geocentric latitude).
	The heliographic latitude of the sub-Earth point follows by
	converting L,D at time T.

	1971, doy 1.0 : B0 = -3.00629,	L0 = 129.631
		B0 = -3.01   ,	L0 = 129.62  (Nautical Almanac)

 >	using the /Precision keyword in NewcombSun produces worse results
 MODIFICATION HISTORY:
	JUN-1993, Paul Hick (UCSD/CASS)
	FEB-1998, Paul Hick (UCSD/CASS)
	    Replaced /radians keyword by /degrees keyword
	OCT-2006, Paul Hick (UCSD/.CASS; pphick@ucsd.edu)
	    Replaced NewcombSun by big_eph call