  A new sampling methodology based on incomplete cosine expansion series is
presented as an alternative to the traditional sinc function approach.
Numerical integration shows that this methodology is efficient and practical.
Applying the incomplete cosine expansion we obtain a rational approximation of
the complex error function that with the same number of the summation terms
provides an accuracy exceeding the Weideman\text{'}s approximation accuracy by
several orders of the magnitude. Application of the expansion results in an
integration consisting of elementary function terms only. Consequently, this
approach can be advantageous for accurate and rapid computation.
