I'm not sure which forum this would go into, but I'm desperate so I'll just post here. So, I have exactly one day to make a diffraction applet. I know a lot about diffraction, nothing about making applets. I've programmed a tiny bit in python, but never made an actual project before. Here's an email describing what I need to make HI erisedk, Thanks for the questions: Is the simulation supposed to include only single slit diffraction or both single slit and multiple slit (diffraction grating)? Ans: only multiple slits (say 10, for concreteness). And I wouldn’t worry about the single-slit envelope, since the grating slit width is usually small enough that the light diffracts into the forward half-plane. Should it model only a single wavelength of light or should you be able to model any number of wavelengths, including white light? Ans: Just one wavelength. It will be for light, but you don’t need to constrain yourself to that. In particular, the applet I was looking at was http://falstad.com/ripple/ Setup: plane wave 1 plane source, 1 frequency Edit walls, and then put in a periodic grating (at least on my computer there’s a location indicator is the lower left — the slits must be equally spaced and of equal size). Note: Changing the resolution erases any modifications. 2nd note: if you can figure out what the coding for the import file is (just put some walls in and look at the export text), you could do the whole thing by numbers, and it would be very easy to modify to find the best setting. (I have no idea what the second part of the answer means) Are there any very specific controls that you would like to see, that are not commonly available in most applets? Ans: For this I’d be happy with a video (i.e., no controls). Though if there was to be any controls, then controlling the wavelength (to show how different colors diffract in different directions) would be good. These are the details. I'd be so grateful for help, especially, step by step instructions.