PROGRAM D1r1

! Driver for routine flmoon

LIBRARY "flmoon", "julday", "caldat"
DECLARE FUNCTION julday

DIM phase$(4), timstr$(2)

CLEAR
LET tzone = 5
MAT READ phase$
DATA "new moon", "first quarter", "full moon", "last quarter"

MAT READ timstr$
DATA " AM", " PM"

PRINT "Date of the next few phases of the moon"
PRINT "Enter today's date (e.g. 1,31,1982)";
INPUT im, id, iy
PRINT
LET timzon = -tzone / 24

! Approximate number of full moons since January 1900

LET n = int(12.37 * (iy - 1900 + (im - .5) / 12))
LET nph = 2
LET j1 = julday(im, id, iy)

CALL flmoon (n, nph, j2, frac)

LET n = int(n + (j1 - j2) / 28)
PRINT "   Date         Time(est)    Phase"
FOR i = 1 to 20

    CALL flmoon (n, nph, j2, frac)

    LET ifrac = round(24 * (frac + timzon))
    IF ifrac < 0 then
       LET j2 = j2 - 1
       LET ifrac = ifrac + 24
    END IF
    IF ifrac >= 12 then
       LET j2 = j2 + 1
       LET ifrac = ifrac - 12
    ELSE
       LET ifrac = ifrac + 12
    END IF
    IF ifrac > 12 then
       LET ifrac = ifrac - 12
       LET istr = 2
    ELSE
       LET istr = 1
    END IF

    CALL caldat (j2, im, id, iy)

    PRINT using "##": im;
    PRINT using "###": id;
    PRINT using "#####": iy;
    PRINT using "#########": ifrac;
    PRINT timstr$(istr); "     "; phase$(nph + 1)
    IF nph = 3 then
       LET nph = 0
       LET n = n + 1
    ELSE
       LET nph = nph + 1
    END IF

NEXT i

END