Hi Lubos, I don't know a whole lot about transforms however, I do remember one bit of information that may be useful to you: The prefactors in the sine transform (which is of course related to the fourier transform) are actually matters of convention. The sqrt(2/pi) is not always the prefactor! The prefactor is usually chosen to be sqrt(2/pi) so that the inverse transform will also have a prefactor of sqrt(2/pi) and there will be some symmetry in the two formulas so that they look alike and are easier to remember. However, SOMETIMES people chose the transform or inverse transform (I can't recall which) to have a 2/pi prefactor, and the other to have no prefactor. I comes down to a matter of convention and it doesn't matter which one you chose, as long as you are consistent. Please careful and make sure you a certain of the convention chosen and you a consistent in what you code and you will be fine. Hope this helps, Frank PS> Dear Everyone, I am trying to get my email mailing list style fixed so that I don't break mailing list etiquette. Please email me personal to check me if this email sucked. Sorry for my previous mistakes! -- Frank Lagor Ph.D. Candidate Mechanical Engineering and Applied Mechanics University of Pennsylvania