FUNCTION datesec_doy, yr, doy
;+
; FUNCTION:
; DATESEC_DOY
;
; DESCRIPTION:
;
; take args for year and day of year and return
; (double float) seconds since 1 Jan 1970, 00:00 UT.
;
; USAGE:
;
; print, datesec_doy(75, 134)
;
; gives result:
; 1.6925760e+08
;
; NOTES:
; does not handle years past 1999; year must be two digit.
;
; REVISION HISTORY:
;
; @(#)datesec_doy.pro 1.3 01/26/99
; written by Ken Bromund, Space Sciences Lab, Berkeley. May, 1991
;-
IF yr LT 70 THEN yr = yr + 100
WHILE yr GE 200 DO yr = yr - 100
return, (doy-1 + (yr - 70) * 365 + fix((yr - 69) / 4))*86400.d
end