Besides, there are other math libraries that I haven't used. You should be able to find some matrix operation libraries online.
LZ, I already said, if you want matcom, I can send it to you, whether it's free or not, anyway, I haven't paid for it in the previous year! I think it's ok. By the way, OPENCV is also free software under VC++, and there are a lot of matrix operation functions on the Internet. It is a bit troublesome to set up this library. It is a library of image processing and motion analysis, so there are many mathematical functions, but I don't like this library. If you want, I have it.
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Because the lines intersecting the three planes are not parallel, it can be seen that the extension lines of the three intersecting line