Do really long calculations cause problems? what am i doing wrong?[resolved]

[MET777]

heres my code for saving some info to an array

For h = 0 To Shp.ubound
    For i = 0 To Shp.ubound
            gravforcex(h, i) = (Shp(h).Left - Shp(i).Left) * (((Sqr(Sqr((Shp(h).Left - Shp(i).Left) ^ 2 + (Shp(h).Top - Shp(i).Top) ^ 2))) ^ -1 * 500) / (Sqr((Shp(h).Left - Shp(i).Left) ^ 2 + (Shp(h).Top - Shp(i).Top) ^ 2)))
            gravforcey(h, i) = (Shp(h).Top - Shp(i).Top) * (((Sqr(Sqr((Shp(h).Left - Shp(i).Left) ^ 2 + (Shp(h).Top - Shp(i).Top) ^ 2))) ^ -1 * 500) / (Sqr((Shp(h).Left - Shp(i).Left) ^ 2 + (Shp(h).Top - Shp(i).Top) ^ 2)))
    Next i
Next h

on the gravforcex(h,i) = blah line... it gives me an invalid procedure call or argument error.
shp is a shape control array, and its set up correctly... ive tested the top and left properties in other ways and they are working.
if u have any input itd be greatly appreciated