;|-----------------------------------------------------------------|
;|                                                                 |
;|    Subroutine IDM                                               |
;|                                                                 |
;|    extracts basic parameters from Idata.                        |
;|                                                                 |
;|-----------------------------------------------------------------|

pro idm

@gia_var.inc


;Get the no. of icolumns in the HDF file

icolumns=idimsizes(1)
orbitnumber=fix(idata(4,0))
OrbitNum='Orbit NO.'+ strcompress(fix(idata(4,0)))
orbitdate='Date :'+strcompress(idata(1,0))
date=round(idata(1,0))

catch,errorstat
if errorstat ne 0 then begin
	print,'!!!!!'
        print,'Error is ',errorstat
endif


;
;First extract Horinzontal and vertical SDS DATA which is stored in rows 46-109 but reduce 1 since IDL starts arrays with row number 0. 
;That is, we will extract 64 rows between 45 and 108.We'll get all icolumns.
;

sdsstart=45.0
sdsrows=64.0
sdsvel=EXTRAC(idata,sdsstart,0,sdsrows,icolumns)
isdsvel=fix(sdsvel)
iflag=round(100.0*abs(sdsvel-isdsvel))
tsdshvel=fltarr(sdsrows/2,icolumns)
tsdsvvel=fltarr(sdsrows/2,icolumns)
sdstimest=fltarr(icolumns)
sdstimeinc=fltarr(sdsrows)
sdstime=fltarr(sdsrows,icolumns)
tsdshtime=fltarr(sdsrows/2,icolumns)
tsdsvtime=fltarr(sdsrows/2,icolumns)
tsdsdate=fltarr(icolumns)
tsdsut=fltarr(icolumns)
tsdsilat=fltarr(icolumns)
tsdsmlt=fltarr(icolumns)
tsdsalt=fltarr(icolumns)
tsdsglat=fltarr(icolumns)
tsdsglon=fltarr(icolumns)
tsdshline_fit=fltarr(2,icolumns)
tsdsvline_fit=fltarr(2,icolumns)
tsdshvel_fit=fltarr(sdsrows/2,icolumns)
tsdsvvel_fit=fltarr(sdsrows/2,icolumns)
jcnt=0
max2=-1.e3
min2=+1.e3
tmax=1.
tmin=1.e10
;
;Big loop
;
For j=0,icolumns-1 do begin



	Flagsize=Size(where(iflag(*,j) eq 60))
	sdstimest(j)=idata(2,j)
	hcnt=0
	vcnt=0
;
;skip low invariant lats (above), need 32 60s
;

	If (idata(13,j) gt 45) and Flagsize(1) eq 32  then begin

		For i=0,sdsrows-1 do begin

			sdstimeinc(i)=i*4*31.25+75
			sdstime(i,j)=sdstimest(j)+sdstimeinc(i)

			If iflag(i,j) eq 60 then begin    ;HORIZONTAL SDS

				If i eq 0 then begin
					tsdsdate(jcnt)=idata(1,j)
				        tsdsut(jcnt)  =idata(2,j)
				        tsdsalt(jcnt) =idata(9,j)
				        tsdsglat(jcnt)=idata(10,j)
				        tsdsglon(jcnt)=idata(11,j)
				        tsdsmlt(jcnt) =idata(12,j)
				        tsdsilat(jcnt)=idata(13,j)
				Endif
				tsdshvel(hcnt,jcnt)=fix(sdsvel(i,j))


				tsdshtime(hcnt,jcnt)=sdstime(i,j)
      ;tsdshtime(hcnt,jcnt)=sdstime(i,j)/1000.
				hcnt=hcnt+1

			Endif else if iflag(i,j) eq 61 then begin ;vertical SDS
				tsdsvvel(vcnt,jcnt)=fix(sdsvel(i,j))
      ;tsdsvtime(vcnt,jcnt)=sdstime(i,j)/1000.
				tsdsvtime(vcnt,jcnt)=sdstime(i,j)
				vcnt=vcnt+1
				endif

				if (sdsvel(i,j) gt max2) then max2=sdsvel(i,j)
				if (sdsvel(i,j) lt min2) then min2=sdsvel(i,j)
                                if (sdstime(i,j) gt tmax) then tmax=sdstime(i,j)
                                if (sdstime(i,j) lt tmin) then tmin=sdstime(i,j)

			
			
 
		Endfor

		jcnt=jcnt+1

	Endif ;end of the big if 

Endfor ;end of the big loop
 
;tmin=sdstime(0,0)
;tmax=sdstime(sdsrows-1,icolumns-1)

sdsjcnt=jcnt

if jcnt eq 0 then return

;clean up the zeros

sdshvel=tsdshvel(*,0:jcnt-1)
sdsvvel=tsdsvvel(*,0:jcnt-1)
sdshtime=tsdshtime(*,0:jcnt-1)
sdsvtime=tsdsvtime(*,0:jcnt-1)
sdsdate=tsdsdate(0:jcnt-1)
sdsut=tsdsut(0:jcnt-1)
sdsmlt=tsdsmlt(0:jcnt-1)
sdsilat=tsdsilat(0:jcnt-1)
sdsalt=tsdsalt(0:jcnt-1)
sdsilat=tsdsilat(0:jcnt-1)
sdsmlt=tsdsmlt(0:jcnt-1)
sdsalt=tsdsalt(0:jcnt-1)
sdsglat=tsdsglat(0:jcnt-1)
sdsglon=tsdsglon(0:jcnt-1)



end;--------------------------------------------------------------------------------------