‘How do you use randsample (or maybe something else?) to sample from a distribution?‘
‘Can you define a non-standard distribution as long as you have the formula for the pdf?’
Yes. See Nonparametric and Empirical Probability Distributions for an extensive discussion. The ecdf function can be used to define an empirical distibution. (Getting random numbers from it would likely require inverting its pdf first, and that could be something of a challenge, depending on the distribution.)
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