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Hey, I need to numerically identify discontinuity points for a function given by a general expression (formula). I am able to evaluate the values at any point. I need it to be fast bu not accurate. The goal is to correctly render functions. With my naive algorithm, I get vertical lines on $x=0$ for $1/x$ and $sign(x)$. The types of discontinuities I need to find are like in the functions $sign(x)$ and $1/x$, that is -,+ adjacent polars and step like functions. I would like to avoid false positives like in the function $sin(1/x)$ which may numerically turn out as discontinues as you approach 0.

Thank You!!!

flag	asked Mar 18 2011 at 6:46 Sonia 23●2

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I don't think that this is appropriate for this site. You might have more luck at maths.stackexchange.com – Andrew Stacey Mar 18 2011 at 8:38

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I think this is appropriate for this site. – Paul Tupper Jul 18 2011 at 4:37

Jerry · Accepted Answer · 2011-03-18 08:25:01Z UTC

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It's going to be hard to find a "fast" way of doing this, but there is an algorithm due to Jeff Tupper for reliably sketching discontinuous functions, which you should be able to adapt to your needs.

answered Mar 18 2011 at 8:25

Jerry
36●1

Numerically Identifying Discontinuity

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