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Personally I would add integration and measure theory (the sigma algebra and lebesgue stuff), but there seems no such module?



This is covered towards the end of a typical undergrad pure math real analysis course sequence.


I think that would be more likely to be covered in a pure math program than applied math.


> I think that would be more likely to be covered in a pure math program than applied math.

Integration is pretty basic and used extensively, and I'd say it makes no sense to cover contour integrals within the scope of complex numbers and differential equations but leave out integrals.


Integration is covered in any calculus course, the comment I was replying to do was about Lebesgue integration which is a much more advanced topic that as far as I know is only needed for integrating functions which are so pathological that they probably don't occur in the physical world.


I am no expert here, but as I understand it, measure theory is used as the basis for all modern probability theory for the reason that it simplifies a lot of things as you get to more advanced topics, like Markov chains on general state spaces [1]. So if you want to study Stochastic Processes you probably want to use measure theory. So thus the Lebesgue integral is not just for "pathological" sets (I remember reading somewhere that even the Lebesgue integral still breaks down on some really pathological examples). If you've studied mathematical statistics, you'll typically see proofs for expectations of discrete distributions and continuous distributions. They're typically similar, but different since you're using summation for the one, and integration for the other. When you get to random vectors, you can have weird distributions where some components are discrete and others continuous. Apparently using a measure-theoretic approach to probability, it unifies these into one general theory (again, I'm no expert, this is how I understand it).

[1] https://www.stat.umn.edu/geyer/8501/measure.pdf


The applied math does teach integration: the Riemann integral. Knowing about Lebesgue integration is not really necessary for most of this kind of work.




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