Accuracy of Integral with epsilon

[Thomas Okken]

(10-09-2021 02:27 AM)Paul Dale Wrote:  Clearly one evaluation is sufficient to get the correct answer here. Two might be prudent to verify that it is a constant function. Three perhaps?

It seems what's really being tested here is how the integrator handles the slight noisiness of the function at the low end of the range, when sinh(x) and cosh(x) become large but with opposite signs, so numerical cancellation becomes an issue.